def METHOD_NAME():
    conn = boto3.client("managedblockchain", region_name="us-east-1")
    # Must be 12 digits
    actions = {"Removals": [{"MemberId": "m-ABCDEFGHIJKLMNOP0123456789"}]}
    # Create network - need a good network
    response = conn.create_network(
        Name="testnetwork1",
        Framework="HYPERLEDGER_FABRIC",
        FrameworkVersion="1.2",
        FrameworkConfiguration=helpers.default_frameworkconfiguration,
        VotingPolicy=helpers.default_votingpolicy,
        MemberConfiguration=helpers.default_memberconfiguration,
    )
    network_id = response["NetworkId"]
    member_id = response["MemberId"]
    with pytest.raises(ClientError) as ex:
        conn.create_proposal(NetworkId=network_id, MemberId=member_id, Actions=actions)
    err = ex.value.response["Error"]
    assert err["Code"] == "InvalidRequestException"
    assert "Member ID format specified in proposal is not valid" in err["Message"]