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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 set_copyright_registration(self, registration):
 """Sets the copyright registration. arg: registration (string):
 the new copyright registration raise: InvalidArgument - ``copyright`` is invalid raise: NoAccess - ``Metadata.isReadOnly()`` is ``true`` raise: NullArgument - ``copyright`` is ``null`` *compliance: mandatory -- This method must be implemented.* """

        # Implemented from template for osid.repository.AssetContentForm.set_url_template
        if self.get_copyright_registration_metadata().is_read_only():
            raise NoAccess()
        if not self._is_valid_string(
                registration,
                self.get_copyright_registration_metadata()):
            raise InvalidArgument()
        self._my_map['copyrightRegistration'] = registration