code: def is_pull_request(issue):
      """Return True if the given issue is a pull request."""
      return "pull_request_url" in issue
  
file_path: dipy/tools/github_stats.py
imports: import json
  import re
  import sys
  from datetime import datetime, timedelta
  from subprocess import check_output
  from urllib.request import urlopen
label_desc: Use image node_id 6 for calling a global function with example usage: is_pull_request(issue) and returns: unknown