Some questions to ask potential interviewers to test there knowledge of python. Senior to principle level.

Interview Quiz

Re-write the following to improve performance (assume the lists below could number into the thousands of elements).

list1 = [{'a': 1, 'b': 2}, {'c': 3, 'd': 4}, {'e': 5, 'f': 6}]
list2 = [{'e': 5, 'f': 6}, {'g': 7, 'h': 8}, {'i': 9, 'j': 10}]

common = []
for entry in list1:
    if entry in list2:
        common.append(entry)






What will be returned from the following list comprehension?

[a - b for (a,b) in zip((1,2,3), (1,2,3))]






Although not syntactically incorrect, what is wrong with the following code?

def foo(x=[]):
    x.append(1)
    print x





What does the following print?

a = [1,2,3,4,5]
print a[::-1]






What are the special class methods __enter__ and __exit__ used for?