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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 convert_odt_to_text(filename: str = None, blob: bytes = None, config: TextProcessingConfig = _DEFAULT_CONFIG) -> str: """ Converts an OpenOffice ODT file to text. Pass either a filename or a binary object. """

    # We can't use exactly the same method as for DOCX files, using docx:
    # sometimes that works, but sometimes it falls over with:
    # KeyError: "There is no item named 'word/document.xml' in the archive"
    with get_filelikeobject(filename, blob) as fp:
        z = zipfile.ZipFile(fp)
        tree = ElementTree.fromstring(z.read('content.xml'))
        # ... may raise zipfile.BadZipfile
        textlist = []  # type: List[str]
        for element in tree.iter():
            if element.text:
                textlist.append(element.text.strip())
    return '\n\n'.join(textlist)