code: def set_db_opts(self, dbname="mta4", credentials=True):
          
          from jcvi.utils.db import valid_dbconn, get_profile
  
          self.add_option("--db", default=dbname, dest="dbname",
                  help="Specify name of database to query [default: %default]")
          self.add_option("--connector", default="Sybase", dest="dbconn",
                  choices=valid_dbconn.keys(), help="Specify database connector [default: %default]")
          hostname, username, password = get_profile()
          if credentials:
              self.add_option("--hostname", default=hostname,
                      help="Specify hostname [default: %default]")
              self.add_option("--username", default=username,
                      help="Username to connect to database [default: %default]")
              self.add_option("--password", default=password,
                      help="Password to connect to database [default: %default]")
          self.add_option("--port", type="int",
                  help="Specify port number [default: %default]")
docs: Add db connection specific attributes