> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/python/cpython/llms.txt
> Use this file to discover all available pages before exploring further.

# string - String Operations

> Common string operations and constants

The `string` module provides common string constants and template classes.

## Module Import

```python theme={null}
import string
```

## String Constants

```python theme={null}
import string

# ASCII letters
print(string.ascii_lowercase)  # 'abcdefghijklmnopqrstuvwxyz'
print(string.ascii_uppercase)  # 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
print(string.ascii_letters)    # 'abcd...XYZ'

# Digits
print(string.digits)  # '0123456789'

# Hexadecimal digits
print(string.hexdigits)  # '0123456789abcdefABCDEF'

# Punctuation
print(string.punctuation)  # '!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~'

# Whitespace
print(string.whitespace)  # ' \t\n\r\x0b\x0c'

# Printable characters
print(string.printable)  # All printable ASCII characters
```

## Template Strings

```python theme={null}
from string import Template

# Basic template
template = Template('Hello, $name!')
result = template.substitute(name='Alice')
print(result)  # 'Hello, Alice!'

# With braces
template = Template('${greeting}, $name!')
result = template.substitute(greeting='Hi', name='Bob')
print(result)  # 'Hi, Bob!'

# Safe substitute (no error for missing keys)
template = Template('Hello, $name!')
result = template.safe_substitute()  # Returns 'Hello, $name!'
```

## Formatter

```python theme={null}
import string

# Custom formatter
formatter = string.Formatter()
result = formatter.format('{0}, {1}!', 'Hello', 'World')
print(result)  # 'Hello, World!'
```

## Practical Uses

### Generate Random String

```python theme={null}
import string
import random

def random_string(length=10):
    chars = string.ascii_letters + string.digits
    return ''.join(random.choice(chars) for _ in range(length))

print(random_string())  # 'aB3xK9mP2q'
```

### Password Generator

```python theme={null}
import string
import random

def generate_password(length=12):
    chars = string.ascii_letters + string.digits + string.punctuation
    return ''.join(random.choice(chars) for _ in range(length))

print(generate_password())  # 'aB3!xK9@mP2q'
```

<CardGroup cols={2}>
  <Card title="Built-in Types" href="/library/built-in-types">
    String type
  </Card>

  <Card title="re" href="/library/re">
    Regular expressions
  </Card>
</CardGroup>