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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_value(self, entity):
 """Internal helper to delete the value for this Property from an entity. Note that if no value exists this is a no-op; deleted values will not be serialized but requesting their value will return None (or an empty list in the case of a repeated Property). """

    if self._name in entity._values:
      del entity._values[self._name]