Assignments are made with the equals symbol (=). For equality tests, the same amount (==) is used. You can increase and decrease a value using the += and -= operators, followed by an addendum. This works with many types of data, including strings. You can assign and use multiple variables on the same line.

Some examples are as follows:

>>> variable = 3
>>> variable += 2
>>> variable
5
>>> variable -= 1
>>> variable
4

>>> _string_ = "Hello"
>>> _string_ += " Parallel Programming CookBook Second Edition!"
>>> print (_string_) 
Hello Parallel Programming CookBook Second Edition!