code: def fixed_hessian(point, model=None):
      """
      Returns a fixed Hessian for any chain location.
  
      Parameters
      ----------
      model: Model (optional if in `with` context)
      point: dict
      vars: list
          Variables for which Hessian is to be calculated.
      """
  
      model = modelcontext(model)
      point = Point(point, model=model)
  
      rval = np.ones(DictToArrayBijection.map(point).size) / 10
      return rval
  
file_path: pymc/pymc/tuning/scaling.py
imports: import numpy
  from numpy import exp, log, sqrt
  from pymc.blocking import DictToArrayBijection
  from pymc.model import Point, modelcontext
  from pymc.pytensorf import hessian_diag
  from pymc.util import get_var_name
label_desc: Use image node_id 1 for calling a global function with example usage: fixed_hessian(point, model) and returns: rval