>>> d = {320:1, 321:0, 322:3}
>>> min(d, key=lambda k: d[k]) 
321

>>> d = {320:1, 321:0, 322:3}
>>> min(d, key=lambda k: d[k]) 
321

Min (d.s items()， key=lambda x: x[1])[0]

如果你不确定你没有多个最小值，我建议:

d = {320:1, 321:0, 322:3, 323:0}
print ', '.join(str(key) for min_value in (min(d.values()),) for key in d if d[key]==min_value)

"""Output:
321, 323
"""

对于具有相同最小值的多个键，您可以使用列表推导式:

d = {320:1, 321:0, 322:3, 323:0}

minval = min(d.values())
res = [k for k, v in d.items() if v==minval]

[321, 323]

等价的功能版本:

res = list(filter(lambda x: d[x]==minval, d))

另一种解决具有相同最小值的多个键的方法:

>>> dd = {320:1, 321:0, 322:3, 323:0}
>>>
>>> from itertools import groupby
>>> from operator import itemgetter
>>>
>>> print [v for k,v in groupby(sorted((v,k) for k,v in dd.iteritems()), key=itemgetter(0)).next()[1]]
[321, 323]