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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 has_method(self, key: str) -> bool: """ Return if a method exists for the current instance. # Arguments key: The method name. # Returns: bool: * True if the current instance has the provided method. * False else. """

        return hasattr(self.__class__, key) and callable(getattr(self.__class__, key))