code: def hyper_as_trig(rv):
      """Return an expression containing hyperbolic functions in terms
      of trigonometric functions. Any trigonometric functions initially
      present are replaced with Dummy symbols and the function to undo
      the masking and the conversion back to hyperbolics is also returned. It
      should always be true that::
  
          t, f = hyper_as_trig(expr)
          expr == f(t)
  
      Examples
      ========
  
      >>> from sympy.simplify.fu import hyper_as_trig, fu
      >>> from sympy.abc import x
      >>> from sympy import cosh, sinh
      >>> eq = sinh(x)**2 + cosh(x)**2
      >>> t, f = hyper_as_trig(eq)
      >>> f(fu(t))
      cosh(2*x)
  
      References
      ==========
  
      .. [1] https://en.wikipedia.org/wiki/Hyperbolic_function
      """
      from sympy.simplify.simplify import signsimp
      from sympy.simplify.radsimp import collect
  
      # mask off trig functions
      trigs = rv.atoms(TrigonometricFunction)
      reps = [(t, Dummy()) for t in trigs]
      masked = rv.xreplace(dict(reps))
  
      # get inversion substitutions in place
      reps = [(v, k) for k, v in reps]
  
      d = Dummy()
  
      return _osborne(masked, d), lambda x: collect(
          signsimp(_osbornei(x, d).xreplace(dict(reps))),
          S.ImaginaryUnit,
      )
  
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 35 for calling a global function with example usage: hyper_as_trig(rv) and returns: _osborne,  function