Install the `typing` module from a terminal:

```bash
pip install typing
```

Then import the module in the Python file:

```python
import typing
```

California Polytechnic State University, San Luis Obispo

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Python's `typing` module defines standard notation for function and variable type annotations. These annotations make intended types explicit, improving code readability and providing a consistent way to document code.

Python `typing` Module for Type Annotations

```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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