Remove an item from a dictionary when its key is unknown

Question

What is the best way to remove an item from a dictionary by value, i.e. when the item\'s key is unknown? Here\'s a simple approach:

for key, item in some_di         


        

Answer 1

A simple comparison between del and pop():

import timeit
code = """
results = {'A': 1, 'B': 2, 'C': 3}
del results['A']
del results['B']
"""
print timeit.timeit(code, number=100000)
code = """
results = {'A': 1, 'B': 2, 'C': 3}
results.pop('A')
results.pop('B')
"""
print timeit.timeit(code, number=100000)

result:

0.0329667857143
0.0451040902256

So, del is faster than pop().