"""
You are given two strings and you have to find an index
of the second occurrence of the second string in the
first one.
Let's go through the first example where you need to
find the second occurrence of "s" in a word "sims".
It’s easy to find its first occurrence with a function
index or find which will point out that "s" is the
first symbol in a word "sims" and therefore the index
of the first occurrence is 0. But we have to find the
second "s" which is 4th in a row and that means that
the index of the second occurrence (and the answer to
a question) is 3.

Input: Two strings.
Output: Int or None

Example:
second_index("sims", "s") == 3
second_index("find the river", "e") == 12
second_index("hi", " ") is None
"""

def second_index(text: str, symbol: str):
    if text.count(symbol) > 1:
        index = text.index(symbol)
        return text[index+1:].index(symbol)+(index+1)
    else:
        return None

print('Tests:')
print(second_index("sims", "s"))
print(second_index("find the river", "e"))
print(second_index("hi", " "))
print(second_index("hi mayor", " "))
print(second_index("hi mr Mayor", " "))