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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def user_url(user, bundle):
 """ Filter for a user object. Checks if a user has permission to change other users. """

    if not user:
        return False

    bundle = bundle.admin_site.get_bundle_for_model(User)
    edit = None

    if bundle:
        edit = bundle.get_view_url('main', user)
    return edit