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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 insert(self, item):
        'Insert a new item.  If equal keys are found, add to the left'
        k = self._key(item)
        i = bisect_left(self._keys, k)
        self._keys.insert(i, k)
        self._items.insert(i, item)