def add_relationship_to_entities(rel_map):
    """
    Purpose:
       define entity relationship
    Args:
        rel_map: the relationship map
    Returns:
        graql_insert_query - graql query
    """
    graql_insert_query = (
        "define "
        + rel_map["rel1"]["entity"]
        + " plays "
        + rel_map["rel1"]["role"]
        + "; "
    )
    graql_insert_query += (
        rel_map["rel2"]["entity"] + " plays " + rel_map["rel2"]["role"] + ";"
    )
    return graql_insert_query