[091] 문자열에 있는 문자(열) 개수 구하기(count)

txt = 'A lot of things occur each day, every day.'
word_count1 = txt.count('o')
word_count2 = txt.count('day')
word_count3 = txt.count(' ')
print(word_count1)
print(word_count2)
print(word_count3)