code: def download_bhavcopy(self, d):
          
          # ex_url = "https://www.nseindia.com/content/historical/EQUITIES/2011/NOV/cm08NOV2011bhav.csv.zip"
          url = self.get_bhavcopy_url(d)
          filename = self.get_bhavcopy_filename(d)
          # response = requests.get(url, headers=self.headers)
          response = self.opener.open(Request(url, None, self.headers))
          zip_file_handle = io.BytesIO(response.read())
          zf = zipfile.ZipFile(zip_file_handle)
          try:
              result = zf.read(filename)
          except KeyError:
              result = zf.read(zf.filelist[0].filename)
  
          return result
docs: returns bhavcopy as csv file.