Precompiling standard library python

Decoding the meaning of the precompile standard library feature during python installation

The Python License states that in certain cases, Python may enter a malfunctioning state on an application server. This issue can be resolved by reinstalling Python.

What does «precompile standard library» option mean in python installation?

My goal is to comprehend the various choices available during the installation of Python 3.6. Can you explain the significance of Precompiling the Standard Library in the Custom Python installation and why it is not selected by default?

In case a python library lacks a matching .pyc or if it is outdated compared to the source), python, importing the library will result in generating new bytecode. This action seems to apply to all components in standard library, thus eliminating the need for it to be done during the initial import.

The reason for it not being the default option is unclear to me. My assumption is that it may have minimal impact and some users may not want to dedicate effort to implement it for libraries that they may not utilize.

Libraries in Python, The Python Standard Library contains the exact syntax, semantics, and tokens of Python. It contains built-in modules that provide access to basic …

What does «precompile standard library» option mean in

What does «precompile standard library» option mean in python installation?Helpful? What does «precompile standard library» option mean in …

Is it possible and feasible to compile the entire Python standard library to byte code?

Is there a simple method to pre-«compile» the Python standard library into byte code? Moreover, would this ensure that Python avoids re-«compiling» a file provided that a corresponding .pyc file is present, as long as the standard library remains unaltered?

Regarding an application server, Python, there are instances where it enters a malfunctioning state without any external trigger. The symptoms of this state are as follows:

C:\> python Traceback (most recent call last): File "C:\Python27\lib\site.py", line 563, in main() File "C:\Python27\lib\site.py", line 552, in main aliasmbcs() File "C:\Python27\lib\site.py", line 478, in aliasmbcs enc = locale.getdefaultlocale()[1] AttributeError: 'module' object has no attribute 'getdefaultlocale' 

There are two potential solutions for the issue at hand. One involves re-installing Python, while the other involves deleting corrupted files with a size of 0 bytes. Despite attempting to intentionally create 0-byte files, I was unable to replicate the problem.

It bothers me that the standard library files are compiled to byte code on demand, as this occurs within a process running that includes both Python and native code that may unpredictably crash. I would rather have all Python code pre-compiled, regardless of whether it resolves the aforementioned issue.

To prevent unwanted modifications by Python, the .pyc files should be set to read-only status, which even the administrator cannot change.

Navigate to properties on Windows, proceed to security and then to edit. Then, you can disallow all groups from having any privileges.

Python3 — What does «precompile standard library», 1 Answer. When you import a python library and it doesn’t have a corresponding .pyc file (or it’s out of date compared to the source), python will …

Including Python standard libraries in your distribution

I require certain Python Modules for my PyS60 project, which are not available in the platform’s default Python SDK. Should I be concerned about licensing matters? Do I have to integrate the PSF license into my project?

The licensing for my project is Apache 2.0.

According to the PSF License FAQ:

Is it possible to package Python along with a proprietary application?

The PSF License permits the inclusion of Python in non-open applications, regardless of whether it is modified or unmodified. This is unlike certain open source licenses licenses.

The frequently asked questions section elaborates on the topic of third-party module licensing.

I believe the response is affirmative.

The python license is very open.

• Python is absolutely free, even for commercial use (including resale). You can sell a product written in Python or a product that embeds the Python interpreter. No licensing fees need to be paid for such usage.
• The Open Source Initiative has certified the Python license as Open Source, and includes it on their list of open source licenses.
• There is no GPL-like «copyleft» restriction. Distributing binary-only versions of Python, modified or not, is allowed. There is no requirement to release any of your source code. You can also write extension modules for Python and provide them only in binary form. However, the Python license is compatible with the GPL, according to the Free Software Foundation.
• You cannot remove the PSF’s copyright notice from either the source code or the resulting binary.

Is it possible to embed python without the standard, Without the standard library, Python won’t even start, since it tries to find os.py (in 3.x; string.py in 2.x). On startup, it imports a number of modules, in …

Must Standard libraries for python beginner

As a beginner in Python, I am unsure about the specific modules or classes within standard libraries that would be relevant for me to learn. This is especially important as I am attempting to tackle challenges from a C++ book. Are there any libraries that can simplify my programming process? While there may not be a definitive answer to this question, I have made it a wiki to gather insights from others.

Explore the exceptional blog series named «Python Module of the Week».

Begin with the standard libraries which are essentially a part of Python, since there is ample to comprehend before proceeding to third-party materials.

The module labeled re is essential, while itertools can also be quite useful.

In general, it’s recommended to thoroughly examine the Standard library. Afterwards, consider utilizing wxPython for creating GUIs, numPy for performing computations, Django for developing web applications, and Amara for handling XML. Fortunately, there are numerous Python libraries and modules available, so you can easily find ones that meet your specific requirements.

To solve problems from a C++ book using Python, it is essential to become proficient in Python’s built-in types, particularly its data structures, such as tuple , list , set , and dict . Additionally, mastering its built-in functions, like max , min , sorted , and reversed , is crucial.

Python’s built-in functions have several hidden features that may not be immediately apparent. These include the in keyword, the optional key= argument for list.sort , sequence multiplication and list slicing, the dict(list_of_pairs) constructor, del , tuple unpacking, among others. Discovering and mastering these features can make using Python a truly enjoyable experience.

Refer to collections.defaultdict for additional information. To learn about file I/O and file objects, please read open .

Compilation — Why compile Python code?, The reason some files get compiled automatically is because they are imported; for instance, if you use import mylib.py, Python will compile …

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Precompiled Standard Library In Python And Its Uses

In this article, we will learn about precompiled standard library in python. Simply we are going to learn about .pyc extensions in python. At the end of the article, we will come to know about What is .pyc file? What are the advantages of .pyc files? How to generate .py to .pyc files? Many of us thought .py is an extension to save the files in python. And we don’t have any knowledge about the .pyc extension. After reading this article, we will be clear about it. Let us move to the article.

pyc stands for python compiled files. Python is a combination or package of interpreter and support libraries. Whenever we are installing python, we will get the two things. They are interpreters and support libraries. An interpreter is useful for running a python code. Support libraries contain all those definitions about all built-in functions.

What are pyc files?

pyc files are the byte code representation of the python scripts. These files are automatically generated when we create a python script. This .pyc file contains the “compiled bytecode” of the program. So It converts the source code to byte code only one time. .pyc files speed up the process. pyc files are created only for the files we import.

What are the advantages of .pyc files?

Before interpreting the python code, the scripts are converted to byte codes. Whenever .pyc files are there, they will help to speed up the execution. We don’t need to recompile. The only condition is that if there are .pyc files, there must be corresponding .py files.

Difference between .py and .pyc files

.py contains the source code of the program, and the pyc files contain the byte code of the program. After the compilation of .py files, the .pyc files are generated. The .pyc files are not created for every program that we run. It only generates for the files that we import.

Precompiled Standard Library

Precompiled Standard Library is the .pyc (byte code) files generated for each of the standard libraries in python. It just converts .py code to .pyc code. Simply, it converts source code to byte code. When we import a python library, it doesn’t have corresponding .pyc files. So it will compile “new byte code”. By doing this will speed up the execution of the code. And we don’t need to recompile the byte code.

While installing python, there is an option named precompiled standard library. It is useful to generate .pyc files for standard libraries. In the below image, I highlighted the option.

How to generate .pyc of any other .py files?

1. Using py_compile method

Let us consider we have a python file named “program.py”. Now we are going to compile this program. We have to give the file name of the python, which we have to compile. After seeing the name of the file, it converts the source code into byte code.

Code

import py_compile py_compile. compile("program.py")

It doesn’t generate any output for this. This code creates a byte code for the file. If we want to see the .pyc files, then we have to follow the steps.

• First, open the IDLE python folder. Right-click on it you will find the option like open file location.
• Just open it you will find the folder named __pycache__. In that, you will find many pyc files.
• Now I wrote a source code for program.py. Let us check the corresponding compiled file.

pyc file folder

Now we can see that a pyc file is there in the corresponding location.

2. Using compile all method

Now let us see how to compile all the files present in a python directory in a single time.

Code

import compileall compileall.compile_dir("C:/Users/AppData/Local/Programs/Python/Python39")

This code will compile all the python scripts in a specified directory. “C:/Users/AppData/Local/Programs/Python/Python39” replace it with your python folder path.

3. py_compileall.main()

This method is useful to compile multiple files at the same time.

Code

import py_compile py_compile.main(['program.py','program1.py','program2.py'])

It doesn’t generate any output for this. This code creates a byte code for the file. If we want to see the pyc files, just follow the same method we have done for method one.

Generate pyc files in terminals

Whatever we have done using python programs is possible in terminals also. We can generate a pyc file using terminals also.

Using py_compile method

C:\Users\Username> python -m compile program.py program1.py program2.py

Opening a terminal, you will initially get that prompt symbol. Give the command that is in bold letters. The pyc files will be generated.

Compile_all method in a terminal

C:\Users\Username> python -m compileall 

This will compile all the files in a python directory.

FAQs Related to Precompile Standard Library in Python

Byte code is a machine-level code that is understandable only by computer. These byte codes are automatically generated with a .pyc extension.

pyc stands for python compiled files.

.pyc files will speed up the execution.

Conclusion

Here we have learned about precompiled standard library in python. Now we are all known about the behind-scenes of python. As a good programmer, it is necessary to know What is happening behind the programming language. So we think this article will be useful for all Python programmers.

We hope this is easy to understand. Learn with us:) In case of any queries, ask it in the comments. We will clear you as soon as possible.

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