Addressing Circular Import Errors in Python
In Python, circular imports occur when multiple modules attempt to import each other. This can lead to errors such as "ImportError: Cannot import name X" or "AttributeError: ... (most likely due to a circular import)."
For instance, consider the following code:
main.py:
from entity import Ent
entity.py:
from physics import Physics class Ent: ...
physics.py:
from entity import Ent class Physics: ...
When you run main.py, you will encounter an error:
Traceback (most recent call last): File "main.py", line 2, in <module> from entity import Ent File ".../entity.py", line 5, in <module> from physics import Physics File ".../physics.py", line 2, in <module> from entity import Ent ImportError: cannot import name Ent</module></module></module>
The error is caused by the circular dependency between physics.py and entity.py. Physics.py attempts to import entity.py, which is already initializing.
To resolve this issue, you should remove the dependency to physics.py from the entity.py module. For example, you can modify entity.py as follows:
entity.py:
# Do not import physics.py class Ent: ...
Now, when you run main.py, you should no longer encounter an error.
For further understanding of circular imports, refer to the resources provided in the footnotes.
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