code: def jhk_to_bmag(jmag, hmag, kmag):
      '''Converts given J, H, Ks mags to a B magnitude value.
  
      Parameters
      ----------
  
      jmag,hmag,kmag : float
          2MASS J, H, Ks mags of the object.
  
      Returns
      -------
  
      float
          The converted B band magnitude.
  
      '''
  
      return convert_constants(jmag,hmag,kmag,
                               BJHK,
                               BJH, BJK, BHK,
                               BJ, BH, BKf jhk_to_bmag(jmag, hmag, kmag):
      '''Converts given J, H, Ks mags to a B magnitude value.
  
      Parameters
      ----------
  
      jmag,hmag,kmag : float
          2MASS J, H, Ks mags of the object.
  
      Returns
      -------
  
      float
          The converted B band magnitude.
  
      '''
  
      return convert_constants(jmag,hmag,kmag,
                               BJHK,
                               BJH, BJK, BHK,
                               BJ, BH, BK)
docs: Converts given J, H, Ks mags to a B magnitude value.
  
      Parameters
      ----------
  
      jmag,hmag,kmag : float
          2MASS J, H, Ks mags of the object.
  
      Returns
      -------
  
      float
          The converted B band magnitude.