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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 string_to_state(s):
 """s is a string possibly preceded by > or @."""

    s = lexer(s)
    attrs = {}
    while True:
        if s.cur == '>':
            attrs['start'] = True
            s.pos += 1
        elif s.cur == '@':
            attrs['accept'] = True
            s.pos += 1
        else:
            break
    x = parse_symbol(s)
    parse_end(s)
    return x, attrs