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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 rgb(color,default=(0,0,0)):
 """ return rgb tuple for named color in rgb.txt or a hex color """

    c = color.lower()
    if c[0:1] == '#' and len(c)==7:
        r,g,b = c[1:3], c[3:5], c[5:]
        r,g,b = [int(n, 16) for n in (r, g, b)]
        return (r,g,b)

    if c.find(' ')>-1:    c = c.replace(' ','')
    if c.find('gray')>-1: c = c.replace('gray','grey')
    if c in x11_colors.keys():  return x11_colors[c]
    return default