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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 remove_perm(perm, group):
 """ Removes a permission from a group """

    if not isinstance(perm, Permission):
        try:
            app_label, codename = perm.split('.', 1)
        except ValueError:
            raise ValueError("For global permissions, first argument must be in"
                             " format: 'app_label.codename' (is %r)" % perm)
        perm = Permission.objects.get(content_type__app_label=app_label, codename=codename)

    group.permissions.remove(perm)
    return