Python: Finding a key of dictionary element with the max/ min value

Quite a simple question that can be solved in several ways:
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__author__ = 'swayam'
my_dict = {'a':2, 'b':5, 'c':3, 'd':8, 'e':3}
maxValKey = max(my_dict, key=my_dict.get)
>>> d
minValKey = min(my_dict, key=my_dict.get)
>>> b
What if you need (key, value) pair:
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__author__ = 'swayam'
from operator import itemgetter
maxPair = max(my_dict.iteritems(), key=itemgetter(1))
>>> ('d', 18)
minPair = min(my_dict.iteritems(), key=itemgetter(1))
>>> ('b', 1)
But what if you have several equal smallest or largest values in your dict and you need all of them:
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__author__ = 'swayam'
my_dict = {'a': 2, 'b': 1, 'c': 6, 'd': 18, 'e': 13, 'f': 1, 'g': 18}
vals = my_dict.values()
maxVal, minVal = max(vals), min(vals)
minVals, maxVals = [], []
for k in my_dict.iterkeys():
    if my_dict[k] == maxVal:
        maxVals.append((k, maxVal))
    elif my_dict[k] == minVal:
        minVals.append((k, minVal))
>>> [('d', 18), ('g', 18)]
>>> [('b', 1), ('f', 1)]
Below are more options to do the same:
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__author__ = 'swayam'
min_value = min(my_dict.values())
max_value = max(my_dict.values())
min_result = [(key, value) for key, value in my_dict.iteritems() if value == min_value]
max_result = [(key, value) for key, value in my_dict.iteritems() if value == max_value ]
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__author__ = 'swayam'
from collections import defaultdict
from operator import itemgetter
my_dict = {'a': 2, 'b': 1, 'c': 6, 'd': 18, 'e': 13, 'f': 1, 'g': 18}
def get_res(dVals):
    res = defaultdict(list)
    for k, v in dVals.items():
        res[v].append(k)
    return min(res.items(), key=itemgetter(0)), max(res.items(), key=itemgetter(0))
print get_res(my_dict)
>>> ((1, ['f', 'b']), (18, ['g', 'd']))

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