def get_travis_branch():
if os.environ.get("<STR_LIT>", "<STR_LIT>") == "<STR_LIT:true>":<EOL><INDENT>return os.environ.get("<STR_LIT>", "<STR_LIT>")<EOL><DEDENT>else:<EOL><INDENT>return os.environ.get("<STR_LIT>", "<STR_LIT>")<EOL><DEDENT>
Get the name of the branch that the PR is from.

    Note that this is not simply ``$TRAVIS_BRANCH``. the ``push`` build will
    use the correct branch (the branch that the PR is from) but the ``pr``
    build will use the _target_ of the PR (usually master). So instead, we ask
    for ``$TRAVIS_PULL_REQUEST_BRANCH`` if it's a PR build, and
    ``$TRAVIS_BRANCH`` if it's a push build.