A: As far as python is concerned, *nothing*. You may choose to use either uploader. Codecov recommends **using the bash uploader when possible** as it supports more unique repository setups. Learn more at [codecov/codecov-bash](https://github.com/codecov/codecov-bash>) and [codecov/codecov-python](https://github.com/codecov/codecov-python>).

A: This output is written by running the command `coverage xml` and states that there were no `.coverage` files found.

1. Make sure coverage is enabled. See Enabling Coverage

2. You may need to run `coverage combine` before running Codecov.

3. Using Docker? Please follow this step: [Testing with Docker: Codecov Inside Docker](https://github.com/codecov/support/wiki/Testing-with-Docker#codecov-inside-docker>).

A: **No**, these files contain coverage data but are not properly mapped back to the source code. We rely on `coveragepy` to handle this by calling `coverage xml` in the uploader.