Find letter most frequently occurring as first letter of words in a passage. Case-insensitive, return lowercase.
Implement this function:
def most_occurring_first_letter(passage: str) -> str:
Write the function only — the arguments are read for you and the return value is printed automatically.
Arguments arrive as one Python literal per line, in this order: passage.
Input
'the cat and the dog ate the treat'
Output
't'