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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 _string_from_ip_int(self, ip_int=None):
 """Turns a 128-bit integer into hexadecimal notation. Args: ip_int: An integer, the IP address. Returns: A string, the hexadecimal representation of the address. Raises: ValueError: The address is bigger than 128 bits of all ones. """

        if not ip_int and ip_int != 0:
            ip_int = int(self._ip)

        if ip_int > self._ALL_ONES:
            raise ValueError('IPv6 address is too large')

        hex_str = '%032x' % ip_int
        hextets = []
        for x in range(0, 32, 4):
            hextets.append('%x' % int(hex_str[x:x+4], 16))

        hextets = self._compress_hextets(hextets)
        return ':'.join(hextets)