code: def jhk_to_sdssr(jmag,hmag,kmag):
      '''Converts given J, H, Ks mags to an SDSS r magnitude value.
  
      Parameters
      ----------
  
      jmag,hmag,kmag : float
          2MASS J, H, Ks mags of the object.
  
      Returns
      -------
  
      float
          The converted SDSS r band magnitude.
  
      '''
  
      return convert_constants(jmag,hmag,kmag,
                               SDSSR_JHK,
                               SDSSR_JH, SDSSR_JK, SDSSR_HK,
                               SDSSR_J, SDSSR_H, SDSSR_Kf jhk_to_sdssr(jmag,hmag,kmag):
      '''Converts given J, H, Ks mags to an SDSS r magnitude value.
  
      Parameters
      ----------
  
      jmag,hmag,kmag : float
          2MASS J, H, Ks mags of the object.
  
      Returns
      -------
  
      float
          The converted SDSS r band magnitude.
  
      '''
  
      return convert_constants(jmag,hmag,kmag,
                               SDSSR_JHK,
                               SDSSR_JH, SDSSR_JK, SDSSR_HK,
                               SDSSR_J, SDSSR_H, SDSSR_K)
docs: Converts given J, H, Ks mags to an SDSS r magnitude value.
  
      Parameters
      ----------
  
      jmag,hmag,kmag : float
          2MASS J, H, Ks mags of the object.
  
      Returns
      -------
  
      float
          The converted SDSS r band magnitude.