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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 get_if_addr6(iff):
 """ Returns the main global unicast address associated with provided interface, in human readable form. If no global address is found, None is returned. """

    return next((x[0] for x in in6_getifaddr()
                 if x[2] == iff and x[1] == IPV6_ADDR_GLOBAL), None)