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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 _register(self, name, AttrCls):
 """Register a new attribute to take care of with dump and load Arguments: | ``name`` -- the name to be used in the dump file | ``AttrCls`` -- an attr class describing the attribute """

        if not issubclass(AttrCls, StateAttr):
            raise TypeError("The second argument must a StateAttr instance.")
        if len(name) > 40:
            raise ValueError("Name can count at most 40 characters.")
        self._fields[name] = AttrCls(self._owner, name)