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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 derive_single_object_url_pattern(slug_url_kwarg, path, action):
 """ Utility function called by class methods for single object views """

    if slug_url_kwarg:
        return r'^%s/%s/(?P<%s>[^/]+)/$' % (path, action, slug_url_kwarg)
    else:
        return r'^%s/%s/(?P<pk>\d+)/$' % (path, action)