python - In Python3, how to create a priority queue based on the second element of its sublist -

for example, have list sublists:

a = [[1,83],[2,7],[3,10]] 

i want create priority queue based on second element of a's sublist,which means if use

a.pop() 

the output

[2,7] 

since has smallest second element.

subclassing built-in list:

>>> class mylist(list): ...     def pop(self, index=none): ...         if index none: ...             try: ...                 index = min(enumerate(self), key=lambda x: x[1][1])[0] ...             except valueerror: ...                 # allow empty lists ...                 pass ...         args = () if index none else (index,) ...         return super(mylist, self).pop(*args) ...          ...          >>> l = mylist([[1,83],[2,7],[3,10]]) >>> l.pop() [2, 7] >>> l [[1, 83], [3, 10]] 

hack way works on directly on built-in list instead of custom class:

>>> import gc >>>  >>> def mypop(list_, index=none): ...     if index none: ...         try: ...             index = min(enumerate(list_), key=lambda x: x[1][1])[0] ...         except valueerror: ...             # allow empty lists ...             pass ...     args = () if index none else (index,) ...     return list_.pop(*args) ...  >>> gc.get_referents(list.__dict__)[0]["mypop"] = mypop >>>  >>> l = [[1,83],[2,7],[3,10]] >>> l.mypop() [2, 7] >>> l.mypop() [3, 10] >>> l.mypop() [1, 83] >>> l.mypop() traceback (most recent call last):   file "<stdin>", line 1, in <module>   file "<stdin>", line 9, in mypop indexerror: pop empty list 

^ hey, don't use this, post here fun!