code: def test_create_multipart_upload(mock_client):
      repo = AzureBlobArtifactRepository(TEST_URI, mock_client)
  
      mock_client.url = "some-url"
      mock_client.account_name = "some-account"
      mock_client.credential.account_key = base64.b64encode(
          b"some-key"
      ).decode("utf-8")
  
      create = repo.create_multipart_upload("local_file")
      assert create.upload_id is None
      assert len(create.credentials) == 1
      assert create.credentials[0].url.startswith(
          "some-url/container/some/path/local_file?comp=block"
      )
  
imports: import base64
  import os
  import posixpath
  from unittest import mock
  import pytest
  from azure.storage.blob import BlobPrefix, BlobProperties, BlobServiceClient
  from mlflow.entities.multipart_upload import MultipartUploadPart
  from mlflow.exceptions import MlflowException
  from mlflow.store.artifact.artifact_repository_registry import get_artifact_repository
  from mlflow.store.artifact.azure_blob_artifact_repo import AzureBlobArtifactRepository
label_desc: Use image node_id 15 for calling a global function with example usage: test_create_multipart_upload(mock_client) without return types