code: def slice_of_slice(s, t):
      start1, stop1, step1 = s
      start2, stop2, step2 = t
  
      start = start1 + start2 * step1
      step = step1 * step2
      stop = start1 + step1 * stop2
  
      if stop > stop1:
          raise IndexError()
  
      return start, stop, step
  
file_path: sympy/sympy/matrices/expressions/slice.py
imports: from sympy.matrices.expressions.matexpr import MatrixExpr
  from sympy.core.basic import Basic
  from sympy.core.containers import Tuple
  from sympy.functions.elementary.integers import floor
label_desc: Use image node_id 2 for calling a global function with example usage: slice_of_slice(s, t) and returns: start,  stop,  step