code: def from_callback(cls, cb, ny=None, nparams=None, dep_scaling=1, indep_scaling=1,
                        **kwargs):
          
          return TransformedSys.from_callback(
              cb, ny, nparams,
              dep_transf_cbs=repeat(cls._scale_fw_bw(dep_scaling)),
              indep_transf_cbs=cls._scale_fw_bw(indep_scaling),
              **kwargs
          )
docs: Create an instance from a callback.
  
          Analogous to :func:`SymbolicSys.from_callback`.
  
          Parameters
          ----------
          cb : callable
              Signature rhs(x, y[:], p[:]) -> f[:]
          ny : int
              length of y
          nparams : int
              length of p
          dep_scaling : number (>0) or iterable of numbers
              scaling of the dependent variables (default: 1)
          indep_scaling: number (>0)
              scaling of the independent variable (default: 1)
          \*\*kwargs :
              Keyword arguments passed onto :class:`ScaledSys`.
  
          Examples
          --------
          >>> def f(x, y, p):
          ...     return [p[0]*y[0]**2]
          >>> odesys = ScaledSys.from_callback(f, 1, 1, dep_scaling=10)
          >>> odesys.exprs
          (p_0*y_0**2/10,)