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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 is_color(color):
 """ Checks if supplied object is a valid color spec. """

    if not isinstance(color, basestring):
        return False
    elif RGB_HEX_REGEX.match(color):
        return True
    elif color in COLOR_ALIASES:
        return True
    elif color in cnames:
        return True
    return False