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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 delete_property(self, key):
 """Remove a property from the document. Calling code should use this method to remove properties on the document instead of modifying ``properties`` directly. If there is a property with the name in ``key``, it will be removed. Otherwise, a ``KeyError`` will be thrown. """

        if key in self.RESERVED_ATTRIBUTE_NAMES:
            raise KeyError(key)
        del self.o[key]