diff -r 7ec1cfe19a24 -r a4137aedcb3a src/python_access.rs
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/python_access.rs	Thu Feb 26 09:32:12 2026 -0500
@@ -0,0 +1,65 @@
+/*!
+Wrappers to Python objects.
+*/
+
+use pyo3::types::{PyModule, PyModuleMethods, PyTracebackMethods};
+use pyo3::{pymodule, Bound, PyResult, Python};
+
+use alg_tools::error::DynResult;
+use anyhow::anyhow;
+
+mod diff_mapping;
+mod function;
+mod numpy_array;
+mod plot;
+mod prox_mapping;
+
+//mod measures;
+
+#[allow(unused_imports)]
+pub use diff_mapping::{
+    Basic, Differentiable, DolfinxPyFunctionMarker, NumpyArrayMarker, PythonMapping,
+};
+//pub use pointsource_algs::measures::python::{DiscreteMeasure_1_f64, DiscreteMeasure_2_f64};
+//
+
+#[allow(unused_imports)]
+pub use prox_mapping::HasProx;
+
+#[allow(unused_imports)]
+pub use numpy_array::{NumpyArray_f64, NumpyMatrix_f64, NumpyVector_f64};
+
+#[allow(unused_imports)]
+pub use plot::PythonPlotFactory;
+
+/// Populates the Python module.
+///
+/// Needs to be called with [`pyo3::append_to_inittab`]:
+/// ```
+/// append_to_inittab!(pymod_pointsource_pde);
+/// ```
+/// before initialising the intepreter.
+#[pymodule]
+#[pyo3(name = "pointsource_pde")]
+pub(crate) fn pymod_pointsource_pde(m: &Bound<'_, PyModule>) -> PyResult<()> {
+    m.add_class::<super::experiments::Experiments>()?;
+    m.add_class::<super::experiments::Problem>()?;
+    m.add_class::<super::experiments::RegTermPy>()?;
+    Ok(())
+}
+
+/// Converts a [`PyErr`] error in a [`Results`] error into a string with traceback.
+pub fn process_error<'py, T>(fname: &str, py: Python<'py>, res: PyResult<T>) -> DynResult<T>
+where
+{
+    match res {
+        Ok(res) => Ok(res),
+        Err(e) => Err(match e.traceback(py) {
+            None => anyhow!("Failed Python traceback in {fname}; original error {e}"),
+            Some(r) => match r.format() {
+                Err(e) => anyhow!("Failed Python traceback formatting in {fname}: {e}"),
+                Ok(o) => anyhow!("Python-side error in {fname}: {e}.\n{o}"),
+            },
+        }),
+    }
+}