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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 _is_valid(self, value):
 """Return True if the input value is valid for insertion into the inner list. Args: value: An object about to be inserted. """


        # Entities have an istypeof method that can perform more sophisticated
        # type checking.
        if hasattr(self._type, "istypeof"):
            return self._type.istypeof(value)
        else:
            return isinstance(value, self._type)