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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 find_root_tex_document(base_dir="."):
 """Find the tex article in the current directory that can be considered a root. We do this by searching contents for ``'\documentclass'``. Parameters base_dir : str Directory to search for LaTeX documents, relative to the current working directory. Returns ------- tex_path : str Path to the root tex document relative to the current working directory. """

    log = logging.getLogger(__name__)
    for tex_path in iter_tex_documents(base_dir=base_dir):
        with codecs.open(tex_path, 'r', encoding='utf-8') as f:
            text = f.read()
            if len(docclass_pattern.findall(text)) > 0:
                log.debug("Found root tex {0}".format(tex_path))
                return tex_path
    log.warning("Could not find a root .tex file")
    raise RootNotFound