def parse_colors(s, length=1):
    '''helper for parsing a string that can be either a matplotlib
       color or be a tuple of colors. Returns a tuple of them either
       way.
    '''
    if length and length > 1:
        return parse_ctuple(s,length=length);
    if re.match('^ *{} *$'.format(isrx_s), s):
        #it's just a string.
        return [s];
    elif re.match('^ *{} *$'.format(rgbrx_s), s):
        return [eval(s)];
    else:
        return parse_ctuple(s,length=length);
helper for parsing a string that can be either a matplotlib
       color or be a tuple of colors. Returns a tuple of them either
       way.