function to do dynamic import?

[bambam]

"J. Cliff Dyer" <jcd at sdf.lonestar.org> wrote in message 
news:mailman.371.1189509653.2658.python-list at python.org...
> bambam wrote:
>> import works in the main section of the module, but does
>> not work as I hoped when run inside a function.
>>
>> That is, the modules import correctly, but are not visible to
>> the enclosing (global) scope.
>>
>> Questions:
>> (1) Where can I read an explanation of this?
>> (2) Is there a work around?
>>
>> BTW, sys.modules("filename") shows that the module is
>> loaded, I just don't know how to use it when loaded that
>> way.  Also, if I import again at the global scope, the module
>> name becomes available.
>>
>> Steve.
>>
>> ---
>>
>>>>> def gim():
>>>>>
>> ... exec "import gamel"
>> ...
>>
> All you have done in this function is bind the module to the name gamel
> within the scope of the function.  As soon as the function exits, the
> module goes out of scope.  If you want to use it externally, return the
> module.
>
> def: gim():
>    import gamel
>    return gamel
>>>>> gim()
>>>>>
> This will have to change to
>
> gamel = gim()
>
> and the rest should work as expected.
>>>>> sys.modules["gamel"]
>>>>>
>> <module 'gamel' from 'c:\gamel.pyc'>
>>
>>>>> gamel
>>>>>
>> NameError: name 'gamel' is not defined
>>
>>>>> exec "import gamel"
>>>>> gamel
>>>>>
>> <module 'gamel' from 'c:\gamel.pyc'>
>>
>>
>>
>

 def: gim():
    import gamel
    return gamel

Unfortunately, it needs to do dynamic import: I can't list
all of the possible import modules because they are unknown
until runtime.

Steve.