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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def files_changed():
 """ Return the list of file changed in the current branch compared to `master` """

    with chdir(get_root()):
        result = run_command('git diff --name-only master...', capture='out')
    changed_files = result.stdout.splitlines()

    # Remove empty lines
    return [f for f in changed_files if f]