The Python REPL, IPython, and Jupyter

The Standard REPL: Features, Shortcuts, and History The Python REPL (Read-Eval-Print Loop) is the interactive shell that serves as the primary gateway for many to the Python language. It is an indispensable tool for rapid prototyping, debugging, testing single lines of code, and exploring language features without the overhead of creating a file. Upon executing the python or python3 command in a terminal, you are dropped into this environment, signaled by the primary (>>>) and secondary (...) prompts. Its power lies in its immediacy; each statement is read, evaluated, and its result is printed back to you in a continuous loop, providing instant feedback.

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