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<overview>

<p>A cyclic import is an <code>import</code> which imports another module

and that module imports (possibly indirectly) the module which contains the

<code>import</code> statement.

If all imports in a cyclic import occur at module level, then a module will be

imported when it is part way through its initialization. This may rest in

surprising errors, as parts of the module being imported may not yet exist.

</p>

<p>In addition to the possible errors, cyclic imports indicate that two modules

are circularly dependent. This means that the modules cannot be tested

independently, and it makes it harder to understand the architecture of the system.

</p>

</overview>

<recommendation>

<p>The cycle may be broken by removing any one import. If only one function or

method requires the import, then consider moving that to the other module and

deleting the import. If the two modules are more intimately connected, then move

the inter-dependent parts into a third module and have both the original modules

import that.

</p>

</recommendation>

<references>

<li>Python Language Reference: <a href="http://docs.python.org/2/reference/simple_stmts.html#import">The import statement</a>.</li>

<li>Python: <a href="http://docs.python.org/2/tutorial/modules.html">Modules</a>.</li>

<li> Effbot: <a href="https://web.archive.org/web/20200917011425/https://effbot.org/zone/import-confusion.htm">Import Confusion</a>.</li>

</references>

</qhelp>