code: def __call__(self, x, y, z, u, v):
      try:
          return self.f(x, y, z, u, v)
      except Exception:
          return None
  
imports: from sympy.core.basic import Basic
  from sympy.core.symbol import Symbol, symbols
  from sympy.utilities.lambdify import lambdify
  from .util import interpolate, rinterpolate, create_bounds, update_bounds
  from sympy.utilities.iterables import sift
label_desc: Use image node_id 7 for calling the ColorScheme obj's underlying member method code with example usage: obj.__call__(x, y, z, u, v) and returns: self, None