如何在python中检查此字符或字符串中字符？

char = 'a'
string = 'hello'

if char in string:
    print("Character exists in the string")
else:
    print("Character does not exist in the string")

char = 'a'
string = 'hello'
char_exists = False

for c in string:
    if c == char:
        char_exists = True
        break

if char_exists:
    print("Character exists in the string")
else:
    print("Character does not exist in the string")