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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 add_keyword_from_file(self, keyword_file, encoding="utf-8"):
 """To add keywords from a file Args: keyword_file : path to keywords file encoding : specify the encoding of the file Examples: keywords file format can be like: Raises: IOError: If `keyword_file` path is not valid """

        if not os.path.isfile(keyword_file):
            raise IOError("Invalid file path {}".format(keyword_file))
        with io.open(keyword_file, encoding=encoding) as f:
            for line in f:
                if '=>' in line:
                    keyword, clean_name = line.split('=>')
                    self.add_keyword(keyword, clean_name.strip())
                else:
                    keyword = line.strip()
                    self.add_keyword(keyword)