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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 apply( self, doc_loader, pdf_path=None, clear=True, parallelism=None, progress_bar=True ):
 """Run the Parser. :param doc_loader: An iteratable of ``Documents`` to parse. Typically, one of Fonduer's document preprocessors. :param pdf_path: The path to the PDF documents, if any. This path will override the one used in initialization, if provided. :param clear: Whether or not to clear the labels table before applying these LFs. :type clear: bool :param parallelism: How many threads to use for extraction. This will override the parallelism value used to initialize the Labeler if it is provided. :type parallelism: int :param progress_bar: Whether or not to display a progress bar. The progress bar is measured per document. :type progress_bar: bool """

        super(Parser, self).apply(
            doc_loader,
            pdf_path=pdf_path,
            clear=clear,
            parallelism=parallelism,
            progress_bar=progress_bar,
        )