[Python] Is there a difference in the order of conditions in a python if statement?

Let's take the Leetcode problem, "first letter to appear twice" (https://leetcode.com/problems/first-letter-to-appear-twice/). The general solution that I came up with was to iterate over the string, store the values in a "seen" list, and if the next value is already in the "seen" list, then return that value.

So if I have some code that goes like this:

class Solution:
def repeatedCharacter(self, s: str) -> str:
seen = []
for i in s:
if i in seen:
return i
else:
seen.append(i)



Is it any different (in terms of time or memory) to this:

class Solution:
def repeatedCharacter(self, s: str) -> str:
seen = []
for i in s:
if i not in seen:
seen.append(i)
else:
return i



Is one way actually better/more efficient than the other, or is this just a preference of typing?

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