code: def url_to_text(self, url):
          '''
          Download PDF file and transform its document to string.
  
          Args:
              url:   PDF url.
  
          Returns:
              string.
  
          '''
          path, headers = urllib.request.urlretrieve(url)
          return self.path_to_text(pathf url_to_text(self, url):
          '''
          Download PDF file and transform its document to string.
  
          Args:
              url:   PDF url.
  
          Returns:
              string.
  
          '''
          path, headers = urllib.request.urlretrieve(url)
          return self.path_to_text(path)
docs: Download PDF file and transform its document to string.
  
          Args:
              url:   PDF url.
  
          Returns:
              string.