code: def mpl_imports():
      """Force matplotlib to use agg backend for tests"""
      try:
          import matplotlib as mpl
      except ImportError:
          pass
      else:
          mpl.use("agg")
  
file_path: nipy/nipy/conftest.py
imports: import os
  import tempfile
  from pathlib import Path
  import numpy
  import pytest
label_desc: Use image node_id 2 for calling a global function with example usage: mpl_imports() without return types