def radon_maintainability_parser(stdout, stderr, previous_reports=None):
    """
    Example line: apps/api/urls.py - A
    """
    lines = stdout.split('\n')[:-1]
    summary = {'A': 0, 'B': 0, 'C': 0}
    for line in lines:
        maintainability = line.split(' ')[2]
        assert maintainability in ['A', 'B', 'C']
        summary[maintainability] += 1
    summary['total'] = sum(summary.values())
    return {'stdout': stdout, 'stderr': stderr, 'summary': summary}
