If

x = 10

if x < 0:
    print('negative')
elif x == 0:
    print('zero')
else:
    print('positive')

x = 5
y = 'even' if x % 2 == 0 else 'odd'
print(y)  # odd

####################################################################
a = 1
b = 1

c = a > 0 and b > 0
print(c)  # True

d = a > 0 or b > 0
print(d)  # True

x = 1
y = [1, 2, 3]
if x in y:
    print('in')

if 100 not in y:
    print('not in')

a = 1
b = 2
if not a == b:  # a != b
    print('Not equal')

is_ok = True
if not is_ok:
    print("not ok")

####################################################################
#  0, 0.0, '', [], {}, set() 을 모두 False 로 판정한다.
#  empty string, empty list 판정에 사용할 수 있다.
is_ok = ''
if is_ok:
    print('OK')
else:
    print('No')  # is_ok 가 empty string 이면 False 로 판정

is_empty = None
print(type(is_empty))  # <class 'NoneType'>

if is_empty is not None:
    print('None !!!')

print(1 == True)  # True
print(1 is True)  # False