Since opencv-python version 4.3.0.*, manylinux1 wheels were replaced by manylinux2014 wheels. If your pip is too old, it will try to use the new source distribution introduced in 4.3.0.38 to manually ...
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krikera/python-shell-exp

This project is a lightweight command-line shell emulator written in Python. It implements basic command execution, tab completion, redirection features, command history, and pipeline functionality ...