code: def pinv(a, rtol=None):
      """Compute a pseudo-inverse of a matrix."""
      u, s, vh = np.linalg.svd(a, full_matrices=False)
      del a
      maxS = np.max(s)
      if rtol is None:
          rtol = max(vh.shape + u.shape) * np.finfo(u.dtype).eps
      rank = np.sum(s > maxS * rtol)
      u = u[:, :rank]
      u /= s[:rank]
      return (u @ vh[:rank]).conj().T
  
imports: import inspect
  import operator
  import os
  import warnings
  from contextlib import contextmanager
  from io import StringIO
  from math import log
  from pprint import pprint
  import numpy
label_desc: Use image node_id 21 for calling a global function with example usage: pinv(a, rtol) and returns: unknown