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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 _parse_tokens(tokens):
 """Parse the tokens. This converts the tokens into a form where we can manipulate them more easily. """


    index = 0
    parsed_tokens = []

    num_tokens = len(tokens)
    while index < num_tokens:
        tok = Token(*tokens[index])

        assert tok.token_type != token.INDENT
        if tok.token_type == tokenize.NEWLINE:
            # There's only one newline and it's at the end.
            break

        if tok.token_string in '([{':
            (container, index) = _parse_container(tokens, index)
            if not container:
                return None
            parsed_tokens.append(container)
        else:
            parsed_tokens.append(Atom(tok))

        index += 1

    return parsed_tokens