code: def t_to_z(t_scores, deg_of_freedom):
      """Convert t-scores to z-scores."""
      p_values = scipy.stats.t.sf(t_scores, df=deg_of_freedom)
      z_values = scipy.stats.norm.isf(p_values)
      return z_values
  
imports: import scipy
  from nilearn import plotting
  from nilearn.datasets import fetch_neurovault_ids
  from nilearn.image import get_data, load_img, math_img, new_img_like
label_desc: Use image node_id 1 for calling a global function with example usage: t_to_z(t_scores, deg_of_freedom) and returns: z_values