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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 remove_host_mapping(interface, nexus_ip):
 """Remove host to interface mapping entry from mapping data base."""


    LOG.debug("remove_host_mapping() called")
    session = bc.get_writer_session()
    try:
        mapping = _lookup_one_host_mapping(
                      session=session,
                      if_id=interface,
                      switch_ip=nexus_ip)
        session.delete(mapping)
        session.flush()
    except c_exc.NexusHostMappingNotFound:
        pass