'Extension method for listing all in-progress OSS multipart uploads.
Each multipart upload which has not been committed or aborted is
considered in-progress.
:param container: The container holding the uploads
:type container: :class:`Container`
:keyword prefix: Print only uploads of objects with this prefix
:type prefix: ``str``
:keyword delimiter: The object/key names are grouped based on
being split by this delimiter
:type delimiter: ``str``
:keyword max_uploads: The max uplod items returned for one request
:type max_uploads: ``int``
:return: A generator of OSSMultipartUpload instances.
:rtype: ``generator`` of :class:`OSSMultipartUpload`'

def ex_iterate_multipart_uploads(self, container, prefix=None, delimiter=None, max_uploads=MAX_UPLOADS_PER_RESPONSE):

    if (not self.supports_multipart_upload):
        raise LibcloudError('Feature    not    supported', driver=self)
    request_path = '/?uploads'
    params = {'max-uploads': max_uploads}
    if prefix:
        params['prefix'] = prefix
    if delimiter:
        params['delimiter'] = delimiter
    def finder(node, text):
        return node.findtext(fixxpath(xpath=text, namespace=self.namespace))
    while True:
        response = self.connection.request(request_path, params=params, container=container)
        if (response.status != httplib.OK):
            raise LibcloudError(('Error    fetching    multipart    uploads.    Got    code:    %s' % response.status), driver=self)
        body = response.parse_body()
        for node in body.findall(fixxpath(xpath='Upload', namespace=self.namespace)):
            key = finder(node, 'Key')
            upload_id = finder(node, 'UploadId')
            initiated = finder(node, 'Initiated')
            (yield OSSMultipartUpload(key, upload_id, initiated))
        is_truncated = body.findtext(fixxpath(xpath='IsTruncated', namespace=self.namespace))
        if (is_truncated.lower() == 'false'):
            break
        upload_marker = body.findtext(fixxpath(xpath='NextUploadIdMarker', namespace=self.namespace))
        key_marker = body.findtext(fixxpath(xpath='NextKeyMarker', namespace=self.namespace))
        params['key-marker'] = key_marker
        params['upload-id-marker'] = upload_marker
