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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 add(self, name, definition):
 """ Register a definition to the registry. Existing definitions are replaced silently. :param name: The name which can be used as reference in a validation schema. :type name: :class:`str` :param definition: The definition. :type definition: any :term:`mapping` """

        self._storage[name] = self._expand_definition(definition)