Learn how to quickly format Python code for better readability using a free Python beautifier tool. Save time and write clean, professional code.

Given the doc of str.format_map (but not that of str.format, that is silent about it), I understand why a real dict is actually needed. But the error message is confusing: it is complaining a mapping ...

The newly approved Python Enhancement Proposal 751 gives Python a standard lock file format for specifying the dependencies of projects. Here’s the what, why, and when.