Heap class that implements (almost) all the heapq standard python interface. Added some doctests and magic methods for convenience.

heap.py

import heapq


class Heap(object):
    """
    Heap class implementing the heapq interface + some magic methods.
    Unit Tests:
    >>> h = Heap([1,5,78,2,5,78])
    >>> h
    Heap([1, 2, 78, 5, 5, 78])
    >>> h.pushpop(0)
    0
    >>> h.nlargest(6)
    [78, 78, 5, 5, 2, 1]
    >>> h.nsmallest(6)
    [1, 2, 5, 5, 78, 78]
    >>> h.nlargest(6, lambda x: -x)
    [1, 2, 5, 5, 78, 78]
    >>> [x for x in h]
    [1, 2, 78, 5, 5, 78]
    >>> len(h)
    6
    """
    def __init__(self, container=None, key=None):
        if not container:
            self._heap = []
        else:
            self._heap = list(container)
            heapq.heapify(self._heap)
        self._key = key

    def push(self, item):
        heapq.heappush(self._heap, item)

    def pop(self):
        return heapq.heappop(self._heap)

    def pushpop(self, item):
        return heapq.heappushpop(self._heap, item)

    def nlargest(self, n, key=None):
        if not key:
            key = self._key
        return heapq.nlargest(n, self._heap, key)

    def nsmallest(self, n, key=None):
        if not key:
            key = self._key
        return heapq.nsmallest(n, self._heap, key)

    def __repr__(self):
        return "Heap({0})".format(self._heap.__repr__())

    def __len__(self):
        return len(self._heap)

    def __iter__(self):
        return iter(self._heap)


if __name__ == '__main__':
    import doctest
    doctest.testmod()