Checking Membership in Python

In Python, we can check whether a string or character is a member of another string or not using "in" or "not in" operators.

These two membership operators are described in the table below:

SymbolOperator NameDescription
ininThe result of this operation becomes True if it finds a value in a specified sequence and False otherwise.
not innot inThe result of this operation becomes True if it doesn't find a value in a specified sequence and False otherwise.

While comparing the string, these operators consider uppercase and lowercase letters or strings separately and make case sensitive comparisons.

A Python Program to Know Whether a String Exists in the Main String or Not

Example:
str1 = input('Please enter first string: ')
str2 = input('Please enter second string: ')
if str2 in str1:
    print(str2+' found in the first string.')
else:
    print(str2+' not found in the first string.')
Output:
Please enter first string: We are writing core python
Please enter second string: python
python found in the first string.

The above program takes two input from the keyboard and checks whether the second string found in the first string or not.