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<li><a class="reference internal" href="#">Concrete Objects Layer</a><ul>
<li><a class="reference internal" href="#fundamental-objects">Fundamental Objects</a></li>
<li><a class="reference internal" href="#numeric-objects">Numeric Objects</a></li>
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<section id="concrete-objects-layer">
<span id="concrete"></span><h1>Concrete Objects Layer<a class="headerlink" href="#concrete-objects-layer" title="Link to this heading">¶</a></h1>
<p>The functions in this chapter are specific to certain Python object types.
Passing them an object of the wrong type is not a good idea; if you receive an
object from a Python program and you are not sure that it has the right type,
you must perform a type check first; for example, to check that an object is a
dictionary, use <a class="reference internal" href="dict.html#c.PyDict_Check" title="PyDict_Check"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_Check()</span></code></a>. The chapter is structured like the
“family tree” of Python object types.</p>
<div class="admonition warning">
<p class="admonition-title">Warning</p>
<p>While the functions described in this chapter carefully check the type of the
objects which are passed in, many of them do not check for <code class="docutils literal notranslate"><span class="pre">NULL</span></code> being passed
instead of a valid object. Allowing <code class="docutils literal notranslate"><span class="pre">NULL</span></code> to be passed in can cause memory
access violations and immediate termination of the interpreter.</p>
</div>
<section id="fundamental-objects">
<span id="fundamental"></span><h2>Fundamental Objects<a class="headerlink" href="#fundamental-objects" title="Link to this heading">¶</a></h2>
<p>This section describes Python type objects and the singleton object <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
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<li class="toctree-l1"><a class="reference internal" href="none.html">The <code class="docutils literal notranslate"><span class="pre">None</span></code> Object</a></li>
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<section id="numeric-objects">
<span id="numericobjects"></span><h2>Numeric Objects<a class="headerlink" href="#numeric-objects" title="Link to this heading">¶</a></h2>
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<section id="sequence-objects">
<span id="sequenceobjects"></span><h2>Sequence Objects<a class="headerlink" href="#sequence-objects" title="Link to this heading">¶</a></h2>
<p id="index-1">Generic operations on sequence objects were discussed in the previous chapter;
this section deals with the specific kinds of sequence objects that are
intrinsic to the Python language.</p>
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<span id="mapobjects"></span><h2>Container Objects<a class="headerlink" href="#container-objects" title="Link to this heading">¶</a></h2>
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<span id="otherobjects"></span><h2>Function Objects<a class="headerlink" href="#function-objects" title="Link to this heading">¶</a></h2>
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<h2>Other Objects<a class="headerlink" href="#other-objects" title="Link to this heading">¶</a></h2>
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