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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 circle2circle(line):
 """ Parse a string that describes a circle in ds9 format. Parameters line : str A string containing a DS9 region command for a circle. Returns ------- circle : [ra, dec, radius] The center and radius of the circle. """

    words = re.split('[(,\s)]', line)
    ra = words[1]
    dec = words[2]
    radius = words[3][:-1]  # strip the "
    if ":" in ra:
        ra = Angle(ra, unit=u.hour)
    else:
        ra = Angle(ra, unit=u.degree)
    dec = Angle(dec, unit=u.degree)
    radius = Angle(radius, unit=u.arcsecond)
    return [ra.degree, dec.degree, radius.degree]