Python check if module is in use in another file

Question

I want a function to set the random seeds for several known packages.I'd like to create a library function which calls:

tf.set_random_seed(seed)
np.random.seed(seed)
random.seed(seed)

, but only if actually needed. In some cases the caller will be part of a program that uses numpy and in others it won't.

I want a single function, in its own importable file, which will set the random seed of various packages, but not to import the package unless used by the caller.

I can easily work-around this by inserting the method in each caller's file. But, I'm curious if there is a way to do what I want to do.

Can I somehow query the calling function and determine "In your scope, has numpy been imported"? If so, this function would call np.random.seed.

There is an answer in this question related to checking imports of a module from outside of that module: https://stackoverflow.com/questions/4858100/how-to-list-imported-modules — Luke DeLuccia, Jan 09 '19 at 20:39

score 2 · Answer 1 · answered Jan 09 '19 at 21:26

@Luke DeLuccia pointed me in the correct direction. For future readers, The code might look something like this:

import sys
def set_pseudoseeds(seed):
    # random
    try:
        module = sys.modules['random']
    except KeyError:
        pass
    else:
        module.seed(seed)
    ...

Thanks Luke!

Python check if module is in use in another file

1 Answers1