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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 find_ge_index(self, k):
        'Return first item with a key >= equal to k.  Raise ValueError if not found'
        i = bisect_left(self._keys, k)
        if i != len(self):
            return i
        raise ValueError('No item found with key at or above: %r' % (k,))