Chapter 7: Standard Library and Tools

This chapter covers essential Python standard library modules and development tools, including collections, itertools, typing, datetime, json, logging, regex, debugging, and testing.

7.1 collections Module

• collections Overview
• namedtuple
• defaultdict
• Counter
• deque
• OrderedDict and ChainMap

7.2 itertools Module

• itertools Overview
• Infinite Iterators (count, cycle, repeat)
• chain and chain.from_iterable
• islice
• product
• permutations and combinations
• groupby
• starmap
• tee
• accumulate
• zip_longest
• compress and filterfalse
• takewhile and dropwhile
• itertools Recipes

7.3 typing Module

• typing Overview
• Basic Annotations (int, str, list)
• Optional and Union
• List[int] vs list[int]
• Callable and TypeAlias
• TypeVar and Generic
• TypeGuard and TypeNarrowing
• TYPE_CHECKING and Forward References
• Practical Type Hint Patterns

7.4 datetime Module

• datetime Overview
• date, time, datetime Objects
• timedelta Arithmetic
• Formatting (strftime) and Parsing (strptime)
• Timezone Handling (timezone, zoneinfo)
• calendar Module
• Practical Patterns

7.5 json Module

• json Overview
• json.dumps and json.loads
• json.dump and json.load (File I/O)
• Formatting and Pretty Printing
• Custom Encoders (JSONEncoder)
• Custom Decoders (object_hook)
• JSON and Python Type Mapping

7.6 logging Module

• logging Overview
• Log Levels
• Logger Objects
• Handlers (Stream, File, Rotating)
• Formatters
• Configuration (dictConfig, fileConfig)
• Logging Best Practices

7.7 Modules Deep Dive

• sys.path and Module Search
• Relative Imports
• Package Init Files
• Package Creation
• Command Line Arguments

7.8 os and sys Modules

• os Module Overview
• File System Operations (os)
• Environment Variables (os.environ)
• Process Management (os)
• os.path vs pathlib
• sys Module Overview
• sys.argv and sys.exit
• sys Runtime Information

7.9 Package Managers

• conda and Anaconda
• conda-forge and Miniforge
• mamba
• Homebrew
• Comparison

7.10 Regular Expressions

• re Module Overview
• Pattern Syntax Basics
• Character Classes
• Quantifiers and Anchors
• Groups and Capturing
• search, match, findall
• sub and split
• Compiling Patterns
• Lookahead and Lookbehind
• Practical Examples

7.11 Debugging

• breakpoint() and pdb Basics
• Common pdb Commands
• Post-Mortem Debugging
• IDE Debugging Overview

7.12 Testing

• Testing Overview
• unittest Basics
• unittest.TestCase Methods
• pytest Basics
• pytest Fixtures
• pytest Parametrize
• Mocking (unittest.mock)
• Test Organization and Best Practices