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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_requested_spec(self, obj, spec_name):
 """Helper to translate user specifications to needed objects."""

        requested = self._specs_in[spec_name]
        if isinstance(requested, str):
            return _get_attr_by_tag(obj, requested, spec_name)
        else:
            return requested