Решение задач Code Wars на Python. Detect Pangram. 6 kyu

A pangram is a sentence that contains every single letter of the alphabet at least once. For example, the sentence "The quick brown fox jumps over the lazy dog" is a pangram, because it uses the letters A-Z at least once (case is irrelevant).
Given a string, detect whether or not it is a pangram. Return True if it is, False if not. Ignore numbers and punctuation.

Разбор задач с Code Wars:
Разбор задач по Python (Питон):
"Поколение Python": курс для профессионалов -