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README.md

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-# fenics-pymc3 · [![Build](https://github.com/ivanyashchuk/fenics-pymc3/workflows/CI/badge.svg)](https://github.com/ivanyashchuk/fenics-pymc3/actions?query=workflow%3ACI+branch%3Amaster) [![Coverage Status](https://coveralls.io/repos/github/IvanYashchuk/fenics-pymc3/badge.svg?branch=master)](https://coveralls.io/github/IvanYashchuk/fenics-pymc3?branch=master) [![DOI](https://zenodo.org/badge/269920875.svg)](https://zenodo.org/badge/latestdoi/269920875)
+# fenics-pymc3 · [![Build](https://github.com/ivanyashchuk/fenics-pymc3/workflows/CI/badge.svg)](https://github.com/ivanyashchuk/fenics-pymc3/actions?query=workflow%3ACI+branch%3Amaster) [![codecov](https://codecov.io/gh/IvanYashchuk/fenics-pymc3/branch/master/graph/badge.svg?token=Y5ULDQD9L8)](https://codecov.io/gh/IvanYashchuk/fenics-pymc3) [![DOI](https://zenodo.org/badge/269920875.svg)](https://zenodo.org/badge/latestdoi/269920875)
 
 This package enables use of [FEniCS](https://fenicsproject.org/) or [Firedrake](https://firedrakeproject.org/)  for solving differentiable variational problems in [PyMC3](https://docs.pymc.io/).