Access raw datastream content from a Fedora object.
    Returns :class:`~django.http.HttpResponse` for HEAD requests,
    :class:`~django.http.StreamingHttpResponse` for GET requests.  The
    headers and status code from Fedora response are set on the
    django response; any headers specified in the parameters will
    override Fedora headers.  If an HTTP_RANGE header is present on the
    request, it is passed through to Fedora.

    This view method is wrapped with ETag and last modified conditionals.

    :param request: HttpRequest
    :param pid: Fedora object PID
    :param dsid: datastream ID
    :param repo: :class:`~eulcore.django.fedora.server.Repository` instance to use,
        in case your application requires custom repository initialization (optional)
    :param headers: dictionary of additional headers to include in the response
    :param as_of_date: access a historical version of the datastream

def raw_datastream(request, pid, dsid, repo=None, headers=None,
       as_of_date=None):
    '''
    Access raw datastream content from a Fedora object.
    Returns :class:`~django.http.HttpResponse` for HEAD requests,
    :class:`~django.http.StreamingHttpResponse` for GET requests.  The
    headers and status code from Fedora response are set on the
    django response; any headers specified in the parameters will
    override Fedora headers.  If an HTTP_RANGE header is present on the
    request, it is passed through to Fedora.

    This view method is wrapped with ETag and last modified conditionals.

    :param request: HttpRequest
    :param pid: Fedora object PID
    :param dsid: datastream ID
    :param repo: :class:`~eulcore.django.fedora.server.Repository` instance to use,
        in case your application requires custom repository initialization (optional)
    :param headers: dictionary of additional headers to include in the response
    :param as_of_date: access a historical version of the datastream
    '''
    return _raw_datastream(request, pid, dsid, repo=repo, headers=headers,
       as_of_date=as_of_date)