code: def TR6(rv, max=4, pow=False):
      """Replacement of cos**2 with 1 - sin(x)**2.
  
      See _TR56 docstring for advanced use of ``max`` and ``pow``.
  
      Examples
      ========
  
      >>> from sympy.simplify.fu import TR6
      >>> from sympy.abc import x
      >>> from sympy import cos
      >>> TR6(cos(x)**2)
      1 - sin(x)**2
      >>> TR6(cos(x)**-2)  #unchanged
      cos(x)**(-2)
      >>> TR6(cos(x)**4)
      (1 - sin(x)**2)**2
      """
      return _TR56(rv, cos, sin, lambda x: 1 - x, max=max, pow=pow)
  
imports: from collections import defaultdict
  from sympy.core.add import Add
  from sympy.core.expr import Expr
  from sympy.core.exprtools import Factors, gcd_terms, factor_terms
  from sympy.core.function import expand_mul
  from sympy.core.mul import Mul
  from sympy.core.numbers import pi, I
  from sympy.core.power import Pow
  from sympy.core.singleton import S
  from sympy.core.sorting import ordered
  from sympy.core.symbol import Dummy
  from sympy.core.sympify import sympify
  from sympy.core.traversal import bottom_up
  from sympy.functions.combinatorial.factorials import binomial
  from sympy.functions.elementary.hyperbolic import cosh, sinh, tanh, coth, sech, csch, HyperbolicFunction
  from sympy.functions.elementary.trigonometric import cos, sin, tan, cot, sec, csc, sqrt, TrigonometricFunction
  from sympy.ntheory.factor_ import perfect_power
  from sympy.polys.polytools import factor
  from sympy.strategies.tree import greedy
  from sympy.strategies.core import identity, debug
  from sympy import SYMPY_DEBUG
label_desc: Use image node_id 9 for calling a global function with example usage: TR6(rv, max, pow) and returns: _TR56