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  <div class="section" id="module-tornado.options">
<span id="tornado-options-command-line-parsing"></span><h1><code class="docutils literal"><span class="pre">tornado.options</span></code> &#8212; Command-line parsing<a class="headerlink" href="#module-tornado.options" title="Permalink to this headline"></a></h1>
<p>A command line parsing module that lets modules define their own options.</p>
<p>Each module defines its own options which are added to the global
option namespace, e.g.:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">tornado.options</span> <span class="k">import</span> <span class="n">define</span><span class="p">,</span> <span class="n">options</span>

<span class="n">define</span><span class="p">(</span><span class="s2">&quot;mysql_host&quot;</span><span class="p">,</span> <span class="n">default</span><span class="o">=</span><span class="s2">&quot;127.0.0.1:3306&quot;</span><span class="p">,</span> <span class="n">help</span><span class="o">=</span><span class="s2">&quot;Main user DB&quot;</span><span class="p">)</span>
<span class="n">define</span><span class="p">(</span><span class="s2">&quot;memcache_hosts&quot;</span><span class="p">,</span> <span class="n">default</span><span class="o">=</span><span class="s2">&quot;127.0.0.1:11011&quot;</span><span class="p">,</span> <span class="n">multiple</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span>
       <span class="n">help</span><span class="o">=</span><span class="s2">&quot;Main user memcache servers&quot;</span><span class="p">)</span>

<span class="k">def</span> <span class="nf">connect</span><span class="p">():</span>
    <span class="n">db</span> <span class="o">=</span> <span class="n">database</span><span class="o">.</span><span class="n">Connection</span><span class="p">(</span><span class="n">options</span><span class="o">.</span><span class="n">mysql_host</span><span class="p">)</span>
    <span class="o">...</span>
</pre></div>
</div>
<p>The <code class="docutils literal"><span class="pre">main()</span></code> method of your application does not need to be aware of all of
the options used throughout your program; they are all automatically loaded
when the modules are loaded.  However, all modules that define options
must have been imported before the command line is parsed.</p>
<p>Your <code class="docutils literal"><span class="pre">main()</span></code> method can parse the command line or parse a config file with
either:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">tornado</span><span class="o">.</span><span class="n">options</span><span class="o">.</span><span class="n">parse_command_line</span><span class="p">()</span>
<span class="c1"># or</span>
<span class="n">tornado</span><span class="o">.</span><span class="n">options</span><span class="o">.</span><span class="n">parse_config_file</span><span class="p">(</span><span class="s2">&quot;/etc/server.conf&quot;</span><span class="p">)</span>
</pre></div>
</div>
<p>Command line formats are what you would expect (<code class="docutils literal"><span class="pre">--myoption=myvalue</span></code>).
Config files are just Python files. Global names become options, e.g.:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">myoption</span> <span class="o">=</span> <span class="s2">&quot;myvalue&quot;</span>
<span class="n">myotheroption</span> <span class="o">=</span> <span class="s2">&quot;myothervalue&quot;</span>
</pre></div>
</div>
<p>We support <a class="reference external" href="/usr/share/doc/python3-doc/html/library/datetime.html#datetime.datetime" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">datetimes</span></code></a>, <a class="reference external" href="/usr/share/doc/python3-doc/html/library/datetime.html#datetime.timedelta" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">timedeltas</span></code></a>, ints, and floats (just pass a <code class="docutils literal"><span class="pre">type</span></code> kwarg to
<a class="reference internal" href="#tornado.options.define" title="tornado.options.define"><code class="xref py py-obj docutils literal"><span class="pre">define</span></code></a>). We also accept multi-value options. See the documentation for
<a class="reference internal" href="#tornado.options.define" title="tornado.options.define"><code class="xref py py-obj docutils literal"><span class="pre">define()</span></code></a> below.</p>
<p><a class="reference internal" href="#tornado.options.options" title="tornado.options.options"><code class="xref py py-obj docutils literal"><span class="pre">tornado.options.options</span></code></a> is a singleton instance of <a class="reference internal" href="#tornado.options.OptionParser" title="tornado.options.OptionParser"><code class="xref py py-obj docutils literal"><span class="pre">OptionParser</span></code></a>, and
the top-level functions in this module (<a class="reference internal" href="#tornado.options.define" title="tornado.options.define"><code class="xref py py-obj docutils literal"><span class="pre">define</span></code></a>, <a class="reference internal" href="#tornado.options.parse_command_line" title="tornado.options.parse_command_line"><code class="xref py py-obj docutils literal"><span class="pre">parse_command_line</span></code></a>, etc)
simply call methods on it.  You may create additional <a class="reference internal" href="#tornado.options.OptionParser" title="tornado.options.OptionParser"><code class="xref py py-obj docutils literal"><span class="pre">OptionParser</span></code></a>
instances to define isolated sets of options, such as for subcommands.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p>By default, several options are defined that will configure the
standard <a class="reference external" href="/usr/share/doc/python3-doc/html/library/logging.html#module-logging" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">logging</span></code></a> module when <a class="reference internal" href="#tornado.options.parse_command_line" title="tornado.options.parse_command_line"><code class="xref py py-obj docutils literal"><span class="pre">parse_command_line</span></code></a> or <a class="reference internal" href="#tornado.options.parse_config_file" title="tornado.options.parse_config_file"><code class="xref py py-obj docutils literal"><span class="pre">parse_config_file</span></code></a>
are called.  If you want Tornado to leave the logging configuration
alone so you can manage it yourself, either pass <code class="docutils literal"><span class="pre">--logging=none</span></code>
on the command line or do the following to disable it in code:</p>
<div class="last highlight-default"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">tornado.options</span> <span class="k">import</span> <span class="n">options</span><span class="p">,</span> <span class="n">parse_command_line</span>
<span class="n">options</span><span class="o">.</span><span class="n">logging</span> <span class="o">=</span> <span class="kc">None</span>
<span class="n">parse_command_line</span><span class="p">()</span>
</pre></div>
</div>
</div>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 4.3: </span>Dashes and underscores are fully interchangeable in option names;
options can be defined, set, and read with any mix of the two.
Dashes are typical for command-line usage while config files require
underscores.</p>
</div>
<div class="section" id="global-functions">
<h2>Global functions<a class="headerlink" href="#global-functions" title="Permalink to this headline"></a></h2>
<dl class="function">
<dt id="tornado.options.define">
<code class="descclassname">tornado.options.</code><code class="descname">define</code><span class="sig-paren">(</span><em>name</em>, <em>default=None</em>, <em>type=None</em>, <em>help=None</em>, <em>metavar=None</em>, <em>multiple=False</em>, <em>group=None</em>, <em>callback=None</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#define"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.define" title="Permalink to this definition"></a></dt>
<dd><p>Defines an option in the global namespace.</p>
<p>See <a class="reference internal" href="#tornado.options.OptionParser.define" title="tornado.options.OptionParser.define"><code class="xref py py-obj docutils literal"><span class="pre">OptionParser.define</span></code></a>.</p>
</dd></dl>

<dl class="data">
<dt id="tornado.options.options">
<code class="descclassname">tornado.options.</code><code class="descname">options</code><a class="headerlink" href="#tornado.options.options" title="Permalink to this definition"></a></dt>
<dd><p>Global options object.  All defined options are available as attributes
on this object.</p>
</dd></dl>

<dl class="function">
<dt id="tornado.options.parse_command_line">
<code class="descclassname">tornado.options.</code><code class="descname">parse_command_line</code><span class="sig-paren">(</span><em>args=None</em>, <em>final=True</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#parse_command_line"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.parse_command_line" title="Permalink to this definition"></a></dt>
<dd><p>Parses global options from the command line.</p>
<p>See <a class="reference internal" href="#tornado.options.OptionParser.parse_command_line" title="tornado.options.OptionParser.parse_command_line"><code class="xref py py-obj docutils literal"><span class="pre">OptionParser.parse_command_line</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="tornado.options.parse_config_file">
<code class="descclassname">tornado.options.</code><code class="descname">parse_config_file</code><span class="sig-paren">(</span><em>path</em>, <em>final=True</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#parse_config_file"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.parse_config_file" title="Permalink to this definition"></a></dt>
<dd><p>Parses global options from a config file.</p>
<p>See <a class="reference internal" href="#tornado.options.OptionParser.parse_config_file" title="tornado.options.OptionParser.parse_config_file"><code class="xref py py-obj docutils literal"><span class="pre">OptionParser.parse_config_file</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="tornado.options.print_help">
<code class="descclassname">tornado.options.</code><code class="descname">print_help</code><span class="sig-paren">(</span><em>file=sys.stderr</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#print_help"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.print_help" title="Permalink to this definition"></a></dt>
<dd><p>Prints all the command line options to stderr (or another file).</p>
<p>See <a class="reference internal" href="#tornado.options.OptionParser.print_help" title="tornado.options.OptionParser.print_help"><code class="xref py py-obj docutils literal"><span class="pre">OptionParser.print_help</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="tornado.options.add_parse_callback">
<code class="descclassname">tornado.options.</code><code class="descname">add_parse_callback</code><span class="sig-paren">(</span><em>callback</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#add_parse_callback"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.add_parse_callback" title="Permalink to this definition"></a></dt>
<dd><p>Adds a parse callback, to be invoked when option parsing is done.</p>
<p>See <a class="reference internal" href="#tornado.options.OptionParser.add_parse_callback" title="tornado.options.OptionParser.add_parse_callback"><code class="xref py py-obj docutils literal"><span class="pre">OptionParser.add_parse_callback</span></code></a></p>
</dd></dl>

<dl class="exception">
<dt id="tornado.options.Error">
<em class="property">exception </em><code class="descclassname">tornado.options.</code><code class="descname">Error</code><a class="reference internal" href="_modules/tornado/options.html#Error"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.Error" title="Permalink to this definition"></a></dt>
<dd><p>Exception raised by errors in the options module.</p>
</dd></dl>

</div>
<div class="section" id="optionparser-class">
<h2>OptionParser class<a class="headerlink" href="#optionparser-class" title="Permalink to this headline"></a></h2>
<dl class="class">
<dt id="tornado.options.OptionParser">
<em class="property">class </em><code class="descclassname">tornado.options.</code><code class="descname">OptionParser</code><a class="reference internal" href="_modules/tornado/options.html#OptionParser"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser" title="Permalink to this definition"></a></dt>
<dd><p>A collection of options, a dictionary with object-like access.</p>
<p>Normally accessed via static functions in the <a class="reference internal" href="#module-tornado.options" title="tornado.options"><code class="xref py py-obj docutils literal"><span class="pre">tornado.options</span></code></a> module,
which reference a global instance.</p>
<dl class="method">
<dt id="tornado.options.OptionParser.items">
<code class="descname">items</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.items"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.items" title="Permalink to this definition"></a></dt>
<dd><p>A sequence of (name, value) pairs.</p>
<div class="versionadded">
<p><span class="versionmodified">New in version 3.1.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.groups">
<code class="descname">groups</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.groups"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.groups" title="Permalink to this definition"></a></dt>
<dd><p>The set of option-groups created by <code class="docutils literal"><span class="pre">define</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified">New in version 3.1.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.group_dict">
<code class="descname">group_dict</code><span class="sig-paren">(</span><em>group</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.group_dict"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.group_dict" title="Permalink to this definition"></a></dt>
<dd><p>The names and values of options in a group.</p>
<p>Useful for copying options into Application settings:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">tornado.options</span> <span class="k">import</span> <span class="n">define</span><span class="p">,</span> <span class="n">parse_command_line</span><span class="p">,</span> <span class="n">options</span>

<span class="n">define</span><span class="p">(</span><span class="s1">&#39;template_path&#39;</span><span class="p">,</span> <span class="n">group</span><span class="o">=</span><span class="s1">&#39;application&#39;</span><span class="p">)</span>
<span class="n">define</span><span class="p">(</span><span class="s1">&#39;static_path&#39;</span><span class="p">,</span> <span class="n">group</span><span class="o">=</span><span class="s1">&#39;application&#39;</span><span class="p">)</span>

<span class="n">parse_command_line</span><span class="p">()</span>

<span class="n">application</span> <span class="o">=</span> <span class="n">Application</span><span class="p">(</span>
    <span class="n">handlers</span><span class="p">,</span> <span class="o">**</span><span class="n">options</span><span class="o">.</span><span class="n">group_dict</span><span class="p">(</span><span class="s1">&#39;application&#39;</span><span class="p">))</span>
</pre></div>
</div>
<div class="versionadded">
<p><span class="versionmodified">New in version 3.1.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.as_dict">
<code class="descname">as_dict</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.as_dict"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.as_dict" title="Permalink to this definition"></a></dt>
<dd><p>The names and values of all options.</p>
<div class="versionadded">
<p><span class="versionmodified">New in version 3.1.</span></p>
</div>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.define">
<code class="descname">define</code><span class="sig-paren">(</span><em>name</em>, <em>default=None</em>, <em>type=None</em>, <em>help=None</em>, <em>metavar=None</em>, <em>multiple=False</em>, <em>group=None</em>, <em>callback=None</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.define"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.define" title="Permalink to this definition"></a></dt>
<dd><p>Defines a new command line option.</p>
<p>If <code class="docutils literal"><span class="pre">type</span></code> is given (one of str, float, int, datetime, or timedelta)
or can be inferred from the <code class="docutils literal"><span class="pre">default</span></code>, we parse the command line
arguments based on the given type. If <code class="docutils literal"><span class="pre">multiple</span></code> is True, we accept
comma-separated values, and the option value is always a list.</p>
<p>For multi-value integers, we also accept the syntax <code class="docutils literal"><span class="pre">x:y</span></code>, which
turns into <code class="docutils literal"><span class="pre">range(x,</span> <span class="pre">y)</span></code> - very useful for long integer ranges.</p>
<p><code class="docutils literal"><span class="pre">help</span></code> and <code class="docutils literal"><span class="pre">metavar</span></code> are used to construct the
automatically generated command line help string. The help
message is formatted like:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="o">--</span><span class="n">name</span><span class="o">=</span><span class="n">METAVAR</span>      <span class="n">help</span> <span class="n">string</span>
</pre></div>
</div>
<p><code class="docutils literal"><span class="pre">group</span></code> is used to group the defined options in logical
groups. By default, command line options are grouped by the
file in which they are defined.</p>
<p>Command line option names must be unique globally. They can be parsed
from the command line with <a class="reference internal" href="#tornado.options.parse_command_line" title="tornado.options.parse_command_line"><code class="xref py py-obj docutils literal"><span class="pre">parse_command_line</span></code></a> or parsed from a
config file with <a class="reference internal" href="#tornado.options.parse_config_file" title="tornado.options.parse_config_file"><code class="xref py py-obj docutils literal"><span class="pre">parse_config_file</span></code></a>.</p>
<p>If a <code class="docutils literal"><span class="pre">callback</span></code> is given, it will be run with the new value whenever
the option is changed.  This can be used to combine command-line
and file-based options:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">define</span><span class="p">(</span><span class="s2">&quot;config&quot;</span><span class="p">,</span> <span class="nb">type</span><span class="o">=</span><span class="nb">str</span><span class="p">,</span> <span class="n">help</span><span class="o">=</span><span class="s2">&quot;path to config file&quot;</span><span class="p">,</span>
       <span class="n">callback</span><span class="o">=</span><span class="k">lambda</span> <span class="n">path</span><span class="p">:</span> <span class="n">parse_config_file</span><span class="p">(</span><span class="n">path</span><span class="p">,</span> <span class="n">final</span><span class="o">=</span><span class="kc">False</span><span class="p">))</span>
</pre></div>
</div>
<p>With this definition, options in the file specified by <code class="docutils literal"><span class="pre">--config</span></code> will
override options set earlier on the command line, but can be overridden
by later flags.</p>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.parse_command_line">
<code class="descname">parse_command_line</code><span class="sig-paren">(</span><em>args=None</em>, <em>final=True</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.parse_command_line"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.parse_command_line" title="Permalink to this definition"></a></dt>
<dd><p>Parses all options given on the command line (defaults to
<a class="reference external" href="/usr/share/doc/python3-doc/html/library/sys.html#sys.argv" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">sys.argv</span></code></a>).</p>
<p>Note that <code class="docutils literal"><span class="pre">args[0]</span></code> is ignored since it is the program name
in <a class="reference external" href="/usr/share/doc/python3-doc/html/library/sys.html#sys.argv" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">sys.argv</span></code></a>.</p>
<p>We return a list of all arguments that are not parsed as options.</p>
<p>If <code class="docutils literal"><span class="pre">final</span></code> is <code class="docutils literal"><span class="pre">False</span></code>, parse callbacks will not be run.
This is useful for applications that wish to combine configurations
from multiple sources.</p>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.parse_config_file">
<code class="descname">parse_config_file</code><span class="sig-paren">(</span><em>path</em>, <em>final=True</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.parse_config_file"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.parse_config_file" title="Permalink to this definition"></a></dt>
<dd><p>Parses and loads the Python config file at the given path.</p>
<p>If <code class="docutils literal"><span class="pre">final</span></code> is <code class="docutils literal"><span class="pre">False</span></code>, parse callbacks will not be run.
This is useful for applications that wish to combine configurations
from multiple sources.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 4.1: </span>Config files are now always interpreted as utf-8 instead of
the system default encoding.</p>
</div>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 4.4: </span>The special variable <code class="docutils literal"><span class="pre">__file__</span></code> is available inside config
files, specifying the absolute path to the config file itself.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.print_help">
<code class="descname">print_help</code><span class="sig-paren">(</span><em>file=None</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.print_help"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.print_help" title="Permalink to this definition"></a></dt>
<dd><p>Prints all the command line options to stderr (or another file).</p>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.add_parse_callback">
<code class="descname">add_parse_callback</code><span class="sig-paren">(</span><em>callback</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.add_parse_callback"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.add_parse_callback" title="Permalink to this definition"></a></dt>
<dd><p>Adds a parse callback, to be invoked when option parsing is done.</p>
</dd></dl>

<dl class="method">
<dt id="tornado.options.OptionParser.mockable">
<code class="descname">mockable</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="reference internal" href="_modules/tornado/options.html#OptionParser.mockable"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#tornado.options.OptionParser.mockable" title="Permalink to this definition"></a></dt>
<dd><p>Returns a wrapper around self that is compatible with
<a class="reference external" href="/usr/share/doc/python3-doc/html/library/unittest.mock.html#unittest.mock.patch" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">mock.patch</span></code></a>.</p>
<p>The <a class="reference external" href="/usr/share/doc/python3-doc/html/library/unittest.mock.html#unittest.mock.patch" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">mock.patch</span></code></a> function (included in
the standard library <a class="reference external" href="/usr/share/doc/python3-doc/html/library/unittest.mock.html#module-unittest.mock" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">unittest.mock</span></code></a> package since Python 3.3,
or in the third-party <code class="docutils literal"><span class="pre">mock</span></code> package for older versions of
Python) is incompatible with objects like <code class="docutils literal"><span class="pre">options</span></code> that
override <code class="docutils literal"><span class="pre">__getattr__</span></code> and <code class="docutils literal"><span class="pre">__setattr__</span></code>.  This function
returns an object that can be used with <a class="reference external" href="/usr/share/doc/python3-doc/html/library/unittest.mock.html#unittest.mock.patch.object" title="(in Python v3.5)"><code class="xref py py-obj docutils literal"><span class="pre">mock.patch.object</span></code></a> to modify option values:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="k">with</span> <span class="n">mock</span><span class="o">.</span><span class="n">patch</span><span class="o">.</span><span class="n">object</span><span class="p">(</span><span class="n">options</span><span class="o">.</span><span class="n">mockable</span><span class="p">(),</span> <span class="s1">&#39;name&#39;</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span>
    <span class="k">assert</span> <span class="n">options</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="n">value</span>
</pre></div>
</div>
</dd></dl>

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