def image_url(
        self,
        width: Optional[int] = None,
        height: Optional[int] = None,
        placeholder_url: Optional[str] = None,
    ) -> str:
        """
        Returns URL to placeholder image
        Example: http://placehold.it/640x480

        :param width: Optional image width
        :param height: Optional image height
        :param placeholder_url: Optional template string of image URLs from custom
            placeholder service. String must contain ``{width}`` and ``{height}``
            placeholders, eg: ``https:/example.com/{width}/{height}``.
        :rtype: str
        """
        width_ = width or self.random_int(max=1024)
        height_ = height or self.random_int(max=1024)
        if placeholder_url is None:
            placeholder_url = self.random_element(self.image_placeholder_services)
        return placeholder_url.format(width=width_, height=height_)

        Returns URL to placeholder image
        Example: http://placehold.it/640x480

        :param width: Optional image width
        :param height: Optional image height
        :param placeholder_url: Optional template string of image URLs from custom
            placeholder service. String must contain ``{width}`` and ``{height}``
            placeholders, eg: ``https:/example.com/{width}/{height}``.
        :rtype: str
        
faker/providers/internet/__init__.py