Python - Opposite of dictionary search [duplicate]

Question

>>>Dictionary[key]

The above statement returns the first corresponding value of the 'key' from the 'Dictionary' but is there a function that does the opposite, i.e. search for the key by it's value

Answer 1

You can write simple lambda for this:

d={"a":5, "bf": 55, "asf": 55}

search_key = lambda in_d, val: (k for k,v in in_d.items() if v == val)

for k in search_key(d, 55):
    print(k)

# since the lambda returns generator expression you can simply print
# the keys as follows:

print(list(search_key(d, 55)))  
# or get the key list
key_list = list(search_key(d, 55))

Gives:

asf
bf