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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 is_request_sent(request, relation='ceph'):
 """Check to see if a functionally equivalent request has already been sent Returns True if a similair request has been sent @param request: A CephBrokerRq object """

    states = get_request_states(request, relation=relation)
    for rid in states.keys():
        if not states[rid]['sent']:
            return False

    return True