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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 get_one_optional(self, name):
 """ Gets one optional dependency by its name. :param name: the dependency name to locate. :return: a dependency reference or null of the dependency was not found """

        locator = self._locate(name)
        return self._references.get_one_optional(locator) if locator != None else None