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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def user_registries(fs0, fs1):
 """Returns the list of user registries present on both FileSystems."""

    for user in fs0.ls('{}Users'.format(fs0.fsroot)):
        for path in user_registries_path(fs0.fsroot, user):
            if fs1.exists(path):
                yield path