Python: Fetch error while loading external packages

[morgan9e]

While running workerd with Python external packages, it omits error below.
(Build: main@3596152)

Loading fastapi, starlette, anyio, sniffio, openssl, pydantic, typing-extensions, pydantic-core, annotated-types
RR
Error in makeHandler
TypeError: response.body.arrayBuffer is not a function
    at loadBundle (pyodide-internal:loadPackage:37:29)
    at async Promise.all (index 6)
    at async loadPackages (pyodide-internal:loadPackage:81:19)
    at async pyodide:python-entrypoint-helper:87:5
    at async setupPackages (pyodide:python-entrypoint-helper:85:10)
    at async pyodide:python-entrypoint-helper:113:7
    at async preparePython (pyodide:python-entrypoint-helper:129:22)
    at async pyodide:python-entrypoint-helper:139:21
    at async Object.fetch (pyodide:python-entrypoint-helper:137:26)

Isn't it should be response.arrayBuffer()?