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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def radec_hmstodd(ra, dec):
 """ Function to convert HMS values into decimal degrees. This function relies on the astropy.coordinates package to perform the conversion to decimal degrees. Parameters ra : list or array List or array of input RA positions dec : list or array List or array of input Dec positions Returns ------- pos : arr Array of RA,Dec positions in decimal degrees Notes ----- This function supports any specification of RA and Dec as HMS or DMS; specifically, the formats:: ["nn","nn","nn.nn"] "nn nn nn.nnn" "nn:nn:nn.nn" "nnH nnM nn.nnS" or "nnD nnM nn.nnS" See Also -------- astropy.coordinates """

    hmstrans = string.maketrans(string.ascii_letters,
                                ' ' * len(string.ascii_letters))

    if isinstance(ra, list):
        rastr = ':'.join(ra)
    elif isinstance(ra, float):
        rastr = None
        pos_ra = ra
    elif ra.find(':') < 0:
        # convert any non-numeric characters to spaces
        # (we already know the units)
        rastr = ra.translate(hmstrans).strip()
        rastr = rastr.replace('  ', ' ')
        # convert 'nn nn nn.nn' to final 'nn:nn:nn.nn' string
        rastr = rastr.replace(' ', ':')
    else:
        rastr = ra

    if isinstance(dec, list):
        decstr = ':'.join(dec)
    elif isinstance(dec, float):
        decstr = None
        pos_dec = dec
    elif dec.find(':') < 0:
        decstr = dec.translate(hmstrans).strip()
        decstr = decstr.replace('  ', ' ')
        decstr = decstr.replace(' ', ':')
    else:
        decstr = dec

    if rastr is None:
        pos = (pos_ra, pos_dec)
    else:
        pos_coord = coords.SkyCoord(rastr + ' ' + decstr,
                                    unit=(u.hourangle, u.deg))
        pos = (pos_coord.ra.deg, pos_coord.dec.deg)
    return pos