def METHOD_NAME(request_body):
    '''Converts an object into a request body.  If it's None
    we'll return an empty string, if it's one of our objects it'll
    convert it to XML and return it.  Otherwise we just use the object
    directly'''
    if request_body is None:
        return b''
    # TODO: check if this is used
    if isinstance(request_body, WindowsAzureData):
        request_body = _convert_class_to_xml(request_body)
    if isinstance(request_body, bytes):
        return request_body
    if isinstance(request_body, _unicode_type):
        return request_body.encode('utf-8')
    request_body = str(request_body)
    if isinstance(request_body, _unicode_type):
        return request_body.encode('utf-8')
    return request_body