def sanitize(string):
    """
    Sanitizes a string so that it can be used as part of a filename
    """
    string = string.strip().lower()
    string = string.replace(' ', '_').replace('feat.', 'feat').replace('ft.',
        'ft')
    string = string.replace('/', '').replace(',', '').replace('’', '')
    string = string.replace("'", '').replace('&', '').replace('__', '_')
    return string
