28. 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:

• 28.1. sys — System-specific parameters and functions
• 28.2. sysconfig — Provide access to Python’s configuration information
  • 28.2.1. Configuration variables
  • 28.2.2. Installation paths
  • 28.2.3. Other functions
  • 28.2.4. Using sysconfig as a script
• 28.3. builtins — Built-in objects
• 28.4. __main__ — Top-level script environment
• 28.5. warnings — Warning control
  • 28.5.1. Warning Categories
  • 28.5.2. The Warnings Filter
    • 28.5.2.1. Default Warning Filters
  • 28.5.3. Temporarily Suppressing Warnings
  • 28.5.4. Testing Warnings
  • 28.5.5. Updating Code For New Versions of Python
  • 28.5.6. Available Functions
  • 28.5.7. Available Context Managers
• 28.6. contextlib — Utilities for with-statement contexts
  • 28.6.1. Utilities
  • 28.6.2. Examples and Recipes
    • 28.6.2.1. Supporting a variable number of context managers
    • 28.6.2.2. Simplifying support for single optional context managers
    • 28.6.2.3. Catching exceptions from __enter__ methods
    • 28.6.2.4. Cleaning up in an __enter__ implementation
    • 28.6.2.5. Replacing any use of try-finally and flag variables
    • 28.6.2.6. Using a context manager as a function decorator
  • 28.6.3. Single use, reusable and reentrant context managers
    • 28.6.3.1. Reentrant context managers
    • 28.6.3.2. Reusable context managers
• 28.7. abc — Abstract Base Classes
• 28.8. atexit — Exit handlers
  • 28.8.1. atexit Example
• 28.9. traceback — Print or retrieve a stack traceback
  • 28.9.1. TracebackException Objects
  • 28.9.2. StackSummary Objects
  • 28.9.3. FrameSummary Objects
  • 28.9.4. Traceback Examples
• 28.10. __future__ — Future statement definitions
• 28.11. gc — Garbage Collector interface
• 28.12. inspect — Inspect live objects
  • 28.12.1. Types and members
  • 28.12.2. Retrieving source code
  • 28.12.3. Introspecting callables with the Signature object
  • 28.12.4. Classes and functions
  • 28.12.5. The interpreter stack
  • 28.12.6. Fetching attributes statically
  • 28.12.7. Current State of Generators and Coroutines
  • 28.12.8. Code Objects Bit Flags
  • 28.12.9. Command Line Interface
• 28.13. site — Site-specific configuration hook
  • 28.13.1. Readline configuration
  • 28.13.2. Module contents
• 28.14. fpectl — Floating point exception control
  • 28.14.1. Example
  • 28.14.2. Limitations and other considerations