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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 _set(self, name, factory, singleton=False, threadlocal=False):
 """ Add a dependency factory to the registry :param name: Name of dependency :param factory: function/callable that returns dependency :param singleton: When True, makes the dependency a singleton. Factory will only be called on first use, subsequent uses receive a cached value. :param threadlocal: When True, register dependency as a threadlocal singleton, Same functionality as ``singleton`` except :class:`Threading.local` is used to cache return values. """

        name = name or factory.__name__
        factory._giveme_registered_name = name
        dep = Dependency(name, factory, singleton, threadlocal)
        self._registry[name] = dep