docstr: Create a new run for tracking.
code: def create_run(self):
      """Create a new run for tracking."""
      url = self.base_url + "/runs/create"
      # user_id is deprecated and will be removed from the API in a future release
      payload = {
          "experiment_id": self.experiment_id,
          "start_time": get_current_time_millis(),
          "user_id": _get_user_id(),
      }
      r = requests.post(url, json=payload)
      run_id = None
      if r.status_code == 200:
          run_id = r.json()["run"]["info"]["run_uuid"]
      else:
          print("Creating run failed!")
      return run_id
  
file_path: mlflow/examples/rest_api/mlflow_tracking_rest_api.py
imports: import argparse
  import os
  import pwd
  import requests
  from mlflow.utils.time import get_current_time_millis
label_desc: Use image node_id 2 for calling the MLflowTrackingRestApi obj's underlying member method code with example usage: obj.create_run() and returns: run_id