This flag enables Profile guided optimization (PGO) and Link Time Optimization (LTO). Both are expensive optimizations that slow down the build process but yield a significant speed boost (around 10-20% from what I remember reading). The discussion of what these exactly do is beyond my knowledge and probably too broad for a single question. Either … Read more
asyncio.run is a Python 3.7 addition. In 3.5-3.6, your example is roughly equivalent to: import asyncio futures = […] loop = asyncio.get_event_loop() loop.run_until_complete(asyncio.wait(futures))
The SyntaxError: unexpected EOF while parsing means that the end of your source code was reached before all code blocks were completed. A code block starts with a statement like for i in range(100): and requires at least one line afterwards that contains code that should be in it. It seems like you were executing … Read more
JPG does not support transparency – RGBA means Red, Green, Blue, Alpha – Alpha is transparency. You need to discard the Alpha Channel or save as something that supports transparency – like PNG. The Image class has a method convert which can be used to convert RGBA to RGB – after that you will be … Read more
You need to install Microsoft Visual C++ 14.0 to install pycrypto: error: Microsoft Visual C++ 14.0 is required. Get it with “Microsoft Visual C++ Build Tools”: http://landinghub.visualstudio.com/visual-cpp-build-tools In the comments you ask which link to use. Use the link to Visual C++ 2015 Build Tools. That will install Visual C++ 14.0 without installing Visual Studio. … Read more
PEP 487 sets out to take two common metaclass usecases and make them more accessible without having to understand all the ins and outs of metaclasses. The two new features, __init_subclass__ and __set_name__ are otherwise independent, they don’t rely on one another. __init_subclass__ is just a hook method. You can use it for anything you … Read more
How about this x = 3.14159265 print(f’pi = {x:.2f}’) Docs for f-strings
Python base interpreter does require some additional modules. Those are not installed with e.g. Ubuntu 18.04 as default. To solve this we need to first find the python version you’re running. If you have only installed one python version on your system (and you are sure about it) you can skip this step. # from … Read more
Here’s a complete “Ideal 2”. It’s not an f-string—it doesn’t even use f-strings—but it does as requested. Syntax exactly as specified. No security headaches since we are not using eval(). It uses a little class and implements __str__ which is automatically called by print. To escape the limited scope of the class we use the … Read more
Steps to convert .py to .exe in Python 3.6 Install Python 3.6. Install cx_Freeze, (open your command prompt and type pip install cx_Freeze. Install idna, (open your command prompt and type pip install idna. Write a .py program named myfirstprog.py. Create a new python file named setup.py on the current directory of your script. In … Read more