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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 from_pairs(cls, doc, pairs):
 """ Construct an enumeration from an iterable of pairs. :param doc: See `Enum.__init__`. :type pairs: ``Iterable[Tuple[unicode, unicode]]`` :param pairs: Iterable to construct the enumeration from. :rtype: Enum """

        values = (EnumItem(value, desc) for value, desc in pairs)
        return cls(doc=doc, values=values)