To install typing module, paste the following command into your terminal.

```
pip install typing
```

Then, to import the module into your code, be sure to have the following code at the top of your file:

```python
import typing
```

California Polytechnic State University, San Luis Obispo

Typing is a module that defines a standard notation for Python function and variable type annotations. The notations can be used to make code more readable, as well as documenting code in a standard format.

Typing Module

Installing and Importing Typing

```python
from typing import Optional, List, Tuple

def function(param1: Optional[int], param2: List[int]):
     print(param1, param2)

>>> function(None, [12, 45, 1])
#None [12, 45, 1]
# For this example, param1 had an input of None, while 
# param2 had a parameter of type List inputted. 
# The function's output reflects this.

>>> function(12, [1, 2])
#12 [1,2]
# For this example, param1 had an input of type int, while 
# param2 had a parameter of type List inputted. 
# The function's output reflects this.
```
Type annotations made for each parameter will return a TypeError if the parameter is not of the correct type.


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