def t01_SimpleSharing(C, pks, crypto, server):
    """Checks that sharing works in the simplest case of sharing one file."""
    alice = C("alice")
    bob = C("bob")
    alice.upload("k", "v")
    m = alice.share("bob", "k")
    if not isinstance(m, str):
        return 0.0
    bob.receive_share("alice", "k", m)
    return float(bob.download("k") == "v")