docs: def image_to_base64(self, image):
          """
          :param image: One of file object, path, or URL
          :return: Base64 of image
          """
          if isinstance(image, file_):
              return base64.b64encode(image.read())
          elif isinstance(image, basestring):
              if image.startswith("http"):
                  # it's URL
                  return base64.b64encode(requests.get(image).content)
              # it's path
              with open(image) as f:
                  return base64.b64encode(f.read())
  
          raise ValueError("Unrecognizable image param: it must one of"
                           " file object, path or URL, not %s" % type(image))