docs: def update_peak_magnitudes(
              self):
          """*update peak magnitudes*
  
          **Key Arguments:**
              # -
  
          **Return:**
              - None
  
          **Usage:**
              ..  todo::
  
                  - add usage info
                  - create a sublime snippet for usage
                  - write a command-line tool for this method
                  - update package tutorial with command-line tool info if needed
  
              .. code-block:: python
  
                  usage code
  
  
          .. todo ::
  
              - update key arguments values and definitions with defaults
              - update return values and definitions
              - update usage examples and text
              - update docstring text
              - check sublime snippet exists
              - clip any useful text to docs mindmap
              - regenerate the docs and check redendering of this docstring
  
          """
          self.log.debug('starting the ``update_peak_magnitudes`` method')
  
          sqlQuery = self.settings["database settings"][
              "transients"]["transient peak magnitude query"]
  
          sqlQuery = """UPDATE sherlock_crossmatches s,
              (%(sqlQuery)s) t
          SET
              s.transientAbsMag = ROUND(t.mag - IFNULL(direct_distance_modulus,
                              distance_modulus),
                      2)
          WHERE
              IFNULL(direct_distance_modulus,
                      distance_modulus) IS NOT NULL
                  AND t.id = s.transient_object_id;""" % locals()
  
          writequery(
              log=self.log,
              sqlQuery=sqlQuery,
              dbConn=self.transientsDbConn,
          )
  
          self.log.debug('completed the ``update_peak_magnitudes`` method')
          return None