lxml.etree.XMLSyntaxError: Char 0x0 out of allowed range, line 1, column 2

[jacobwegner]

    @lru_cache()
    def render(self):
        xsl_path = os.path.join(os.path.dirname(__file__), settings.XSL_STYLESHEET_PATH)
        with open(xsl_path, "rb") as f:
            func_ns = "urn:python-funcs"
            transform = etree.XSLT(
                etree.XML(f.read()),
                extensions={
                    (func_ns, "tokens"): self.tokens,
                    (func_ns, "token_type"): self.token_type,
                    (func_ns, "token_index"): self.token_index,
                    (func_ns, "token_offset"): self.token_offset,
                },
            )

[jacobwegner]

Need to ensure we're opening file in rb.