"Unlocking Python's Secret Vault: The Mysterious World of __pycache__ Revealed!"
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Introduction:
In Python, the __pycache__
directory is automatically created to store compiled bytecode files (.pyc
files) by the Python interpreter. When a Python script or module is executed, the interpreter translates the source code into bytecode before executing it.
In Python, bytecode is an intermediate representation of the source code that is generated by the Python interpreter. It is not machine code directly understood by the hardware but rather a low-level, platform-independent representation that serves as an intermediate step between the human-readable source code and the machine code executed by the computer.
This bytecode is executed by the Python Virtual Machine (PVM), which is a software abstraction layer that runs on the host machine. The PVM interprets the bytecode and translates it into machine code specific to the underlying hardware.
Here are some key points about the __pycache__
directory:
Location: The
__pycache__
directory is created in the same directory as the Python script or module that is being executed.Python Version Specific: The
__pycache__
directory is version-specific, meaning that it contains bytecode files compiled for a specific version of Python. This helps prevent issues when running the code with a different Python version.File Naming Convention: The
.pyc
files inside__pycache__
are named based on a hash of the source file's path and some other metadata. This ensures that the bytecode files are unique and correspond to the correct source file.Usage: The presence of the
__pycache__
directory helps improve the startup time of Python scripts and modules because the interpreter can use the precompiled bytecode instead of recompiling the source code every time.Ignoring
__pycache__
: In version control systems or when sharing code, the__pycache__
directory is often excluded or ignored. This is because it contains compiled files and doesn't need to be included in the source code repository.
Thank you for reading!
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Aayush Niraula
Aayush Niraula
CS student