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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 chars2str(chars) -> List[str]: """Inversion function of function |str2chars|. ['zeros', 'ones'] [] """

    strings = collections.deque()
    for subchars in chars:
        substrings = collections.deque()
        for char in subchars:
            if char:
                substrings.append(char.decode('utf-8'))
            else:
                substrings.append('')
        strings.append(''.join(substrings))
    return list(strings)