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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 header(self, method, client='htmlshark'):
        '''
        generates Grooveshark API Json header
        '''
        return {'token': self._request_token(method, client),
                'privacy': 0,
                'uuid': self.session.user,
                'clientRevision': grooveshark.const.CLIENTS[client]['version'],
                'session': self.session.session,
                'client': client,
                'country': self.session.country}