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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 equivalent_relshell_type(val):
 """Returns `val`'s relshell compatible type. :param val: value to check relshell equivalent type :raises: `NotImplementedError` if val's relshell compatible type is not implemented. """

        builtin_type = type(val)
        if builtin_type not in Type._typemap:
            raise NotImplementedError("builtin type %s is not convertible to relshell type" %
                                      (builtin_type))
        relshell_type_str = Type._typemap[builtin_type]
        return Type(relshell_type_str)