code: def graymap(X, **kwargs):
      """Same as :func:`heatmap` but uses a gray colormap."""
      return heatmap(X, cmap_type="gray", **kwargs)
  
file_path: innvestigate/src/innvestigate/utils/visualizations.py
imports: from __future__ import annotations
  import matplotlib
  import matplotlib.pyplot
  import numpy
label_desc: Use image node_id 3 for calling a global function with example usage: graymap(X) and returns: heatmap