code: def query_equ(self, ra, dec, d=None, frame='icrs', **kwargs):
          
  
          valid_frames = ['icrs', 'fk4', 'fk5', 'fk4noeterms']
  
          if frame not in valid_frames:
              raise ValueError(
                  '`frame` not understood. Must be one of {}.'.format(valid_frames))
  
          if not isinstance(ra, units.Quantity):
              ra = ra * units.deg
          if not isinstance(dec, units.Quantity):
              dec = dec * units.deg
  
          if d is None:
              coords = coordinates.SkyCoord(ra, dec, frame='icrs')
          else:
              if not isinstance(d, units.Quantity):
                  d = d * units.kpc
              coords = coordinates.SkyCoord(
                  ra, dec,
                  distance=d,
                  frame='icrs')
  
          return self.query(coords, **kwargs)
docs: Query using Equatorial coordinates. By default, the ICRS frame is used,
          although other frames implemented by :obj:`astropy.coordinates` may also be
          specified.
  
          Args:
              ra (:obj:`float`, scalar or array-like): Galactic longitude, in degrees,
                  or as an :obj:`astropy.unit.Quantity`.
              dec (`float`, scalar or array-like): Galactic latitude, in degrees,
                  or as an :obj:`astropy.unit.Quantity`.
              d (Optional[:obj:`float`, scalar or array-like]): Distance from the Solar
                  System, in kpc, or as an :obj:`astropy.unit.Quantity`. Defaults to
                  ``None``, meaning no distance is specified.
              frame (Optional[:obj:`icrs`]): The coordinate system. Can be ``'icrs'`` (the
                  default), ``'fk5'``, ``'fk4'`` or ``'fk4noeterms'``.
              **kwargs: Any additional keyword arguments accepted by derived
                  classes.
  
          Returns:
              The results of the query, which must be implemented by derived
              classes.