Is there any open source tools for RPA (Robotic Process Automation)

We want to build an RPA software.

The definition of RPA: A software ‘robot’ is a software application that replicates the actions of a human being interacting with the user interface of a computer system.

I searched RPA open-source software for several days.

Are there any open-source tools for RPA? I know some commercial software like “BluePrism”, “OpenSpan”, etc.

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