Since it is variable, then the values changes
x = 10
print(y) # name error because y is not defined
y = 20
print(y) # now it is OK :)
names should be nouns or noun phrases
car_speed = 10 # good name
car = 'BMW' # good name
name = 'Ahmed' # good name
a = 10 # bad name
car1 = 'BMW' # good name
1car = 'BMW' # bad name (syntax error )
car$speed = 100 # bad name (syntax error)
x = 10 # assignment
y = x + 3 # expression and assignment
print(2 ** 3) # power: 2*2*2
print(divmod(23, 5)) # (4, 3)
print(23 // 5) # 4
print(23 % 5) # 3
x = 0.6
3.9 * x * ( 1 - x )
x = 10
print(type(x)) # <class 'int'>
x = 10.1
print(type(x)) # <class 'float'>
x = 'abc'
print(type(x)) # <class 'str'>
print(10 / 3) # float result
print(10 / 2) # float result
print('abc' + '123') # concat
print('abc' - 'qwerty') # error
# int to str
print(str(123))
# flaot to str
print(str(12.3))
# str to int
print(int('133'))
print(int('133abc')) # error
print(int('13.3')) # error
# string to flaot
print(float('13.3'))
print(float('13.3.1')) # error