in operator python

# Python Operators
Operator	Name			Example
+			Addition		x + y	
-			Subtraction		x - y	
*			Multiplication	x * y	
/			Division		x / y	
%			Modulus			x % y	
**			Exponentiation	x ** y	
//			Floor division	x // y

//	'a' // 'b'	(Floor Division) Quotient when 'a' is divided by 'b', rounded to the next smallest whole number

# operations in numbers with python 
a = 15
b = 3
#a and b are not expression because they are at the right side

print(a + b)    # this will add the numbers
print(a - b)    # this will subtract the numbers
print(a * b)    # this will multiply the numbers
print(a / b)    #this will divide the numbers
print(a // b)   #this will gives the reminder after division

in operator : The ‘in’ operator is used 
  to check if a value exists in a sequence or not. 
  Evaluates to true if it finds a variable in 
  the specified sequence and false otherwise.