# Python Mimetypes Module

The `mimetypes` module converts between a filename or URL and the MIME type associated with the filename extension. It provides functions to guess the type of a file based on its name or URL, and to guess the extension based on a MIME type.

## Importing the Module

```python
import mimetypes
```

## Guessing MIME Types

The `mimetypes.guess_type()` function guesses the type of a file based on its filename or URL. It returns a tuple `(type, encoding)`.

```python
import mimetypes

filename = 'example.html'
mime_type, encoding = mimetypes.guess_type(filename)

print(f"MIME type: {mime_type}")   # Output: text/html
print(f"Encoding: {encoding}")     # Output: None
```

If the file is compressed, the encoding will be returned.

```python
filename = 'example.tar.gz'
mime_type, encoding = mimetypes.guess_type(filename)

print(f"MIME type: {mime_type}")   # Output: application/x-tar
print(f"Encoding: {encoding}")     # Output: gzip
```

## Guessing Extensions

The `mimetypes.guess_extension()` function guesses the extension for a file based on its MIME type.

```python
import mimetypes

extension = mimetypes.guess_extension('text/html')
print(extension) # Output: .html

extension = mimetypes.guess_extension('application/json')
print(extension) # Output: .json
```

## Adding Custom Types

You can add your own types to the mapping using `add_type()`.

```python
mimetypes.add_type('application/x-my-app', '.myapp')
print(mimetypes.guess_type('file.myapp'))
```

[[programming/python/python]]