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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 _request(self, process=None, wait=None):
 """helper for building pvRequests :param str process: Control remote processing. May be 'true', 'false', 'passive', or None. :param bool wait: Wait for all server processing to complete. """

        opts = []
        if process is not None:
            opts.append('process=%s' % process)
        if wait is not None:
            if wait:
                opts.append('wait=true')
            else:
                opts.append('wait=false')
        return 'field()record[%s]' % (','.join(opts))