30. Python Runtime Services

The modules described in this chapter provide a wide range of services related to the Python interpreter and its interaction with its environment. Here’s an overview:

• 30.1. sys — System-specific parameters and functions
• 30.2. sysconfig — Provide access to Python’s configuration information
  • 30.2.1. Configuration variables
  • 30.2.2. Installation paths
  • 30.2.3. Other functions
  • 30.2.4. Using sysconfig as a script
• 30.3. builtins — Built-in objects
• 30.4. __main__ — Top-level script environment
• 30.5. warnings — Warning control
  • 30.5.1. Warning Categories
  • 30.5.2. The Warnings Filter
    • 30.5.2.1. Describing Warning Filters
    • 30.5.2.2. Default Warning Filter
    • 30.5.2.3. Overriding the default filter
  • 30.5.3. Temporarily Suppressing Warnings
  • 30.5.4. Testing Warnings
  • 30.5.5. Updating Code For New Versions of Dependencies
  • 30.5.6. Available Functions
  • 30.5.7. Available Context Managers
• 30.6. dataclasses — Data Classes
  • 30.6.1. Module-level decorators, classes, and functions
  • 30.6.2. Post-init processing
  • 30.6.3. Class variables
  • 30.6.4. Init-only variables
  • 30.6.5. Frozen instances
  • 30.6.6. Inheritance
  • 30.6.7. Default factory functions
  • 30.6.8. Mutable default values
  • 30.6.9. Exceptions
• 30.7. contextlib — Utilities for with-statement contexts
  • 30.7.1. Utilities
  • 30.7.2. Examples and Recipes
    • 30.7.2.1. Supporting a variable number of context managers
    • 30.7.2.2. Catching exceptions from __enter__ methods
    • 30.7.2.3. Cleaning up in an __enter__ implementation
    • 30.7.2.4. Replacing any use of try-finally and flag variables
    • 30.7.2.5. Using a context manager as a function decorator
  • 30.7.3. Single use, reusable and reentrant context managers
    • 30.7.3.1. Reentrant context managers
    • 30.7.3.2. Reusable context managers
• 30.8. abc — Abstract Base Classes
• 30.9. atexit — Exit handlers
  • 30.9.1. atexit Example
• 30.10. traceback — Print or retrieve a stack traceback
  • 30.10.1. TracebackException Objects
  • 30.10.2. StackSummary Objects
  • 30.10.3. FrameSummary Objects
  • 30.10.4. Traceback Examples
• 30.11. __future__ — Future statement definitions
• 30.12. gc — Garbage Collector interface
• 30.13. inspect — Inspect live objects
  • 30.13.1. Types and members
  • 30.13.2. Retrieving source code
  • 30.13.3. Introspecting callables with the Signature object
  • 30.13.4. Classes and functions
  • 30.13.5. The interpreter stack
  • 30.13.6. Fetching attributes statically
  • 30.13.7. Current State of Generators and Coroutines
  • 30.13.8. Code Objects Bit Flags
  • 30.13.9. Command Line Interface
• 30.14. site — Site-specific configuration hook
  • 30.14.1. Readline configuration
  • 30.14.2. Module contents