d

[Artgalst23]

def count_occurrences(phrase: str, letter: str) -> int:
"""
Implement count_occurrences function:

It takes a phrase and a letter and calculates the number of times
the letter appears in the phrase. The function is case insensitive.

count_occurrences("letter", "t") == 2
count_occurrences("abc", "a") == 1
count_occurrences("abc", "d") == 0
count_occurrences("ABC", "a") == 1

:param phrase: phrase to count in it
:param letter: letter to find occurrences of it
:return: count occurrences of letter in phrase
"""
counter = 0
for char in phrase:
    if char.lower() == letter.lower():
        counter += 1
return counter