code: def validate_max_step(max_step):
      """Assert that max_Step is valid and return it."""
      if max_step <= 0:
          raise ValueError("`max_step` must be positive.")
      return max_step
  
file_path: scipy/scipy/integrate/_ivp/common.py
imports: from itertools import groupby
  from warnings import warn
  import numpy
  from scipy.sparse import find, coo_matrix
label_desc: Use image node_id 2 for calling a global function with example usage: validate_max_step(max_step) and returns: max_step