ToolPythonBeginner py-pde from the ground up: the heat equation on a square plate eq = pde.DiffusionPDE(diffusivity=D, bc=bc)eq_flux = pde.DiffusionPDE(diffusivity=D, bc=bc_flux)pde.DiffusionPDE(diffusivity=D, bc={"x-": {"value": 1}, "y": {"derivative": 0}}).solve(