Question

this is my python code

mylist = ['a', 'f', 'z']
old_d = {'a': 'aaa', 'b': 'bbb', 'c': 'ccc', 'f': 'fff', 'g':'ggg', 'z':'zzz'} 
new_d = {}
for key in mylist:
    new_d[key] = old_d[key]

Can we write the above code using list comprehensions or something similar like

new_d[key] = old_d[key] for key in mylist 

Answer 1

In Python 2.7 and above you can use a dict comprehension:

new_d = {key: old_d[key] for key in myList}

In Python 2.6 and below, you don’t have dict comprehensions must use dict with a generator or list comprehension:

new_d = dict((key, old_d[key]) for key in myList)