The Python programming language is widely used by companies around the world to build web apps, analyze data, automate operations via DevOps and create reliable, scalable enterprise applications.
Uber's tech stack contains a significant amount of Python, which they documented in a series of engineering posts. Part one describes the lower backend levels, which are written in Python, with Node.js, Go and Java mixed in. Part two explains the higher levels of the marketplace and user interfaces.
Facebook and Instagram use Python 3 at scale. They've been very vocal about successfully making the migration from the Python 2 world into Python 3.
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