<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def grepPDF(self, path):
 """ Parse PDF files text content for keywords. Args: path: PDF file path. Returns: match: set of unique occurrences of every match. """

    with open(path, 'rb') as pdf_file_obj:
      match = set()
      text = ''
      pdf_reader = PyPDF2.PdfFileReader(pdf_file_obj)
      pages = pdf_reader.numPages
      for page in range(pages):
        page_obj = pdf_reader.getPage(page)
        text += '\n' + page_obj.extractText()
      match.update(set(x.lower() for x in re.findall(
          self._keywords, text, re.IGNORECASE)))
    return match