<list> = dir(<object>) # Names of object's attributes (incl. methods).

<dict> = vars(<object>) # Dict of object's fields. Also <obj>.__dict__.

<bool> = hasattr(<object>, '<attr_name>') # Checks if getattr() raises an error.

value = getattr(<object>, '<attr_name>') # Raises AttributeError if attribute is missing.

setattr(<object>, '<attr_name>', value) # Only works on objects with __dict__ attribute.

<div><h3 id="attributes-1">Attributes</h3><pre><code class="python language-python hljs">&lt;list&gt; = dir(&lt;object&gt;) <span class="hljs-comment"># Names of object's attributes (incl. methods).</span>

&lt;dict&gt; = vars(&lt;object&gt;) <span class="hljs-comment"># Dict of object's fields. Also &lt;obj&gt;.__dict__.</span>

value = getattr(&lt;object&gt;, <span class="hljs-string">'&lt;attr_name&gt;'</span>) <span class="hljs-comment"># Raises AttributeError if attribute is missing.</span>

setattr(&lt;object&gt;, <span class="hljs-string">'&lt;attr_name&gt;'</span>, value) <span class="hljs-comment"># Only works on objects with __dict__ attribute.</span>

delattr(&lt;object&gt;, <span class="hljs-string">'&lt;attr_name&gt;'</span>) <span class="hljs-comment"># Equivalent to `del &lt;object&gt;.&lt;attr_name&gt;`.</span>

<div><h3 id="parameters-1">Parameters</h3><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> inspect <span class="hljs-keyword">import</span> signature

&lt;sig&gt; = signature(&lt;function&gt;)

no_of_params = len(&lt;sig&gt;.parameters)