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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_echo(cls, request,
                    api_key: (Ptypes.header, String('API key'))) -> [
            (200, 'Ok', String)]:
        '''Echo the header parameter.'''
        log.info('Echoing header param, value is: {}'.format(api_key))
        for i in range(randint(0, MAX_LOOP_DURATION)):
            yield
        msg = 'The value sent was: {}'.format(api_key)
        Respond(200, msg)