Read a blurb file.

Broadly equivalent to blurb.parse(open(filename).read()).

def load(self, filename, *, metadata=None):
        """
Read a blurb file.

Broadly equivalent to blurb.parse(open(filename).read()).
        """
        with open(filename, "rt", encoding="utf-8") as file:
            text = file.read()
        self.parse(text, metadata=metadata, filename=filename)