from ... import vs import . Revisited
The question has arisen regarding the difference between the following code fragments:
<code class="python">from urllib import request</code>
and
<code class="python">import urllib.request</code>
To clarify, these two methods are not interchangeable. The decision between them depends on the desired accessibility of the imported entity.
Using from ... import allows direct access to the imported entity without specifying the module name. For instance,
<code class="python">from urllib import request mine = request()</code>
On the other hand, import . requires specifying the module name when accessing the imported entity.
<code class="python">import urllib.request mine = urllib.request()</code>
Additionally, from ... import allows for aliasing of imports to avoid collisions with built-in functions or other imported entities. For example,
<code class="python">from os import open as open_ mine = open_()</code>
This usage allows one to utilize os.open without overriding the built-in open() function that returns file handles. Ultimately, the choice between these import styles depends on the programmer's preference and the specific context of the code.
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