[demos] make other demos also use `config.require`

src/pymordemos/fenics_nonlinear.py

@@ -5,6 +5,8 @@
 
 from typer import Argument, run
 
+from pymor.core.config import config
+
 
 def main(
     dim: int = Argument(..., help='Spatial dimension of the problem.'),
@@ -13,6 +15,7 @@ def main(
 ):
     """Reduces a FEniCS-based nonlinear diffusion problem using POD/DEIM."""
     from pymor.tools import mpi
+    config.require("FENICS")
 
     if mpi.parallel:
         from pymor.models.mpi import mpi_wrap_model

src/pymordemos/thermalblock_simple.py

@@ -15,6 +15,7 @@ from typer import Argument, run
 
 from pymor.basic import *
 from pymor.tools.typer import Choices
+from pymor.core.config import config
 
 
 # parameters for high-dimensional models
@@ -50,6 +51,7 @@ def main(
     elif model == 'fenics':
         fom, parameter_space = discretize_fenics()
     elif model == 'ngsolve':
+        config.require("NGSOLVE")
         fom, parameter_space = discretize_ngsolve()
     elif model == 'pymor_text':
         fom, parameter_space = discretize_pymor_text()