code: def _generate_sympify_namespace(
      independent_variables, dependent_variables, helper_functions
  ):
        # noqa
  
      independent_variable = independent_variables[0]  # TEMP FIX BEFORE REAL ND
      symbolic_independent_variable = Symbol(independent_variable)
  
      def partial_derivative(symbolic_independent_variable, i, expr):
          return Derivative(expr, symbolic_independent_variable, i)
  
      namespace = {independent_variable: symbolic_independent_variable}
      namespace.update(
          {
              "d%s"
              % (independent_variable * i): partial(
                  partial_derivative, symbolic_independent_variable, i
              )
              for i in range(1, 10)
          }
      )
      namespace.update(
          {
              "d%s%s"
              % (independent_variable * order, var): Derivative(
                  Function(var)(independent_variable), independent_variable, order
              )
              for order, var in product(
                  range(1, 10), dependent_variables + helper_functions
              )
          }
      )
      logging.debug("sympy namespace: %s" % namespace)
      return namespace
docs: Generate the link between the symbols of the derivatives and the
        sympy Derivative operation.
  
        Parameters
        ----------
        independent_variable : str
            name of the independant variable ("x")
        dependent_variables : iterable of str
            names of the dependent variables
        helper_functions : iterable of str
            names of the helper functions
  
        Returns
        -------
        dict
            dictionnary containing the symbol to parse as keys and the sympy expression to evaluate instead as values.