**Each abstract base class specifies a set of virtual subclasses. This classes are then recognized by isinstance() and issubclass() as subclasses of the ABC, although they are really not.**
**Each abstract base class specifies a set of virtual subclasses. These classes are then recognized by isinstance() and issubclass() as subclasses of the ABC, although they are really not.**
```python
>>> from collections.abc import Sequence, Collection, Iterable
@ -1458,7 +1458,7 @@ Exit
```python
import sys
sys.exit() # Exits with exit code 0 (success).
sys.exit(<el>) # Prints object to stderr and exits with 1.
sys.exit(<el>) # Prints to stderr and exits with 1.
<div><h4id="sometypesdonothavebuiltinnamessotheymustbeimported">Some types do not have built-in names, so they must be imported:</h4><pre><codeclass="python language-python hljs"><spanclass="hljs-keyword">from</span> types <spanclass="hljs-keyword">import</span> FunctionType, MethodType, LambdaType, GeneratorType
</code></pre></div>
<div><h3id="abstractbaseclasses">Abstract Base Classes</h3><p><strong>Each abstract base class specifies a set of virtual subclasses. This classes are then recognized by isinstance() and issubclass() as subclasses of the ABC, although they are really not.</strong></p><pre><codeclass="python language-python hljs"><spanclass="hljs-meta">>>></span><spanclass="hljs-keyword">from</span> collections.abc <spanclass="hljs-keyword">import</span> Sequence, Collection, Iterable
<div><h3id="abstractbaseclasses">Abstract Base Classes</h3><p><strong>Each abstract base class specifies a set of virtual subclasses. These classes are then recognized by isinstance() and issubclass() as subclasses of the ABC, although they are really not.</strong></p><pre><codeclass="python language-python hljs"><spanclass="hljs-meta">>>></span><spanclass="hljs-keyword">from</span> collections.abc <spanclass="hljs-keyword">import</span> Sequence, Collection, Iterable
<div><h2id="exit"><ahref="#exit"name="exit">#</a>Exit</h2><p><strong>Exits the interpreter by raising SystemExit exception.</strong></p><pre><codeclass="python language-python hljs"><spanclass="hljs-keyword">import</span> sys
sys.exit() <spanclass="hljs-comment"># Exits with exit code 0 (success).</span>
sys.exit(<el>) <spanclass="hljs-comment"># Prints object to stderr and exits with 1.</span>
sys.exit(<el>) <spanclass="hljs-comment"># Prints to stderr and exits with 1.</span>
sys.exit(<int>) <spanclass="hljs-comment"># Exits with passed exit code.</span>
<li><strong>Levels deeper than 'depth' get replaced with '…'.</strong></li>
<li><strong>Levels deeper than 'depth' get replaced by '…'.</strong></li>
</ul>
<div><h2id="input"><ahref="#input"name="input">#</a>Input</h2><p><strong>Reads a line from the user input or pipe if present.</strong></p><pre><codeclass="python language-python hljs"><str> = input(prompt=<spanclass="hljs-keyword">None</span>)