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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 is_observing_method(self, prop_name, method):
 """ Returns `True` if the given method was previously added as an observing method, either dynamically or via decorator. """

        if (prop_name, method) in self.__PAT_METH_TO_KWARGS:
            return True
        if method in self.__METH_TO_PAT:
            pat = self.__METH_TO_PAT[method]
            if fnmatch.fnmatch(prop_name, pat):
                return True

        return False