Python - Flipping Binary 1's and 0's in a String

Question

I'm trying to take a binary number in string form and flip the 1's and 0's, that is, change all of the 1's in the string to 0's, and all of the 0's to 1's. I'm new to Python and have been racking my brain for several hours now trying to figure it out.

Answer 1

>>> ''.join('1' if x == '0' else '0' for x in '1000110')
'0111001'

The a for b in c pattern is a generator expression, which produces a series of items based on a different series. In this case, the original series is the characters (since you can iterate over strings in Python, which gives you the characters that make up that string), and the new series is a set of characters with the 0's and 1's flipped.

'1' if x == '0' else '0' is pretty straightforward - it gives us whichever of 1 or 0 isn't x. We do this for each such x in the original set of characters, and then join() them all together (with an empty string '', a.k.a. nothing, in between each item), thus giving us a final string which is all of the opposite characters from the original, combined.