<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def read_colortable(fobj):
 r"""Read colortable information from a file. Reads a colortable, which consists of one color per line of the file, where a color can be one of: a tuple of 3 floats, a string with a HTML color name, or a string with a HTML hex color. Parameters fobj : a file-like object A file-like object to read the colors from Returns ------- List of tuples A list of the RGB color values, where each RGB color is a tuple of 3 floats in the range of [0, 1]. """

    ret = []
    try:
        for line in fobj:
            literal = _parse(line)
            if literal:
                ret.append(mcolors.colorConverter.to_rgb(literal))
        return ret
    except (SyntaxError, ValueError):
        raise RuntimeError('Malformed colortable.')