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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(cls, name=None):
 """Gets the application wide depot instance. Might return ``None`` if :meth:`configure` has not been called yet. """

        if name is None:
            name = cls._default_depot

        name = cls.resolve_alias(name)  # resolve alias
        return cls._depots.get(name)