Einsum optimization using opt_einsum and PyTorch FX

opt-einsum-fx is a Python library that leverages opt_einsum and PyTorch FX to optimize Einstein summation (einsum) expressions within PyTorch computation graphs. It aims to reduce the overall execution time and memory footprint of complex tensor contractions by intelligently reordering operations. The current version is 0.1.4, with the last release in November 2021, indicating a maintenance-level release cadence.