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Doc: Try to enhance wording on circular imports. (GH-24705)
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@ -1898,26 +1898,26 @@ How can I have modules that mutually import each other?
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Suppose you have the following modules:
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foo.py::
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:file:`foo.py`::
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from bar import bar_var
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foo_var = 1
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bar.py::
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:file:`bar.py`::
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from foo import foo_var
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bar_var = 2
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The problem is that the interpreter will perform the following steps:
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* main imports foo
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* Empty globals for foo are created
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* foo is compiled and starts executing
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* foo imports bar
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* Empty globals for bar are created
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* bar is compiled and starts executing
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* bar imports foo (which is a no-op since there already is a module named foo)
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* bar.foo_var = foo.foo_var
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* main imports ``foo``
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* Empty globals for ``foo`` are created
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* ``foo`` is compiled and starts executing
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* ``foo`` imports ``bar``
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* Empty globals for ``bar`` are created
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* ``bar`` is compiled and starts executing
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* ``bar`` imports ``foo`` (which is a no-op since there already is a module named ``foo``)
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* The import mechanism tries to read ``foo_var`` from ``foo`` globals, to set ``bar.foo_var = foo.foo_var``
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The last step fails, because Python isn't done with interpreting ``foo`` yet and
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the global symbol dictionary for ``foo`` is still empty.
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