def clean(file_, imports):
    "Remove modules that aren't imported in project from file."
    modules_not_imported = compare_modules(file_, imports)
    re_remove = re.compile('|'.join(modules_not_imported))
    to_write = []
    try:
        f = open_func(file_, 'r+')
    except OSError:
        logging.error('Failed on file: {}'.format(file_))
        raise
    else:
        for i in f.readlines():
            if (re_remove.match(i) is None):
                to_write.append(i)
        f.seek(0)
        f.truncate()
        for i in to_write:
            f.write(i)
    finally:
        f.close()
    logging.info(('Successfully cleaned up requirements in ' + file_))
Remove modules that aren't imported in project from file.
def clean(file_, imports):
    
    modules_not_imported = compare_modules(file_, imports)
    re_remove = re.compile('|'.join(modules_not_imported))
    to_write = []
    try:
        f = open_func(file_, 'r+')
    except OSError:
        logging.error('Failed on file: {}'.format(file_))
        raise
    else:
        for i in f.readlines():
            if (re_remove.match(i) is None):
                to_write.append(i)
        f.seek(0)
        f.truncate()
        for i in to_write:
            f.write(i)
    finally:
        f.close()
    logging.info(('Successfully cleaned up requirements in ' + file_))