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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 relative_to(base, relativee):
 """ Gets 'relativee' relative to 'basepath'. i.e., 'radix' 'Projects/Twisted' The 'relativee' must be a child of 'basepath'. """

    basepath = os.path.abspath(base)
    relativee = os.path.abspath(relativee)
    if relativee.startswith(basepath):
        relative = relativee[len(basepath):]
        if relative.startswith(os.sep):
            relative = relative[1:]
        return os.path.join(base, relative)
    raise ValueError("%s is not a subpath of %s" % (relativee, basepath))