Patch taken from the upstream repository
https://github.com/frescobaldi/python-poppler-qt5/issues/43

From 92e5962ec3751ab051d0b655fd61afc7a1cf709e Mon Sep 17 00:00:00 2001
From: Ben Greiner <code@bnavigator.de>
Date: Thu, 4 Mar 2021 17:02:51 +0100
Subject: [PATCH] map type QVector< QPair<TYPE, TYPE> > for
 FormFieldChoice::choicesWithExportValues() (#45)

---
 types.sip | 93 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 93 insertions(+)

diff --git a/types.sip b/types.sip
index 239b8c9..81cb283 100644
--- a/types.sip
+++ b/types.sip
@@ -331,5 +331,98 @@ template <TYPE>
 };
 
 
+/**
+ * Convert QVector< QPair<TYPE, TYPE> >
+ * from and to a Python list of a 2-item tuple
+ */
+
+template<TYPE>
+%MappedType QVector< QPair<TYPE, TYPE> >
+{
+%TypeHeaderCode
+#include <qvector.h>
+#include <qpair.h>
+%End
+
+%ConvertFromTypeCode
+  // Create the list.
+  PyObject *l;
+
+  if ((l = PyList_New(sipCpp->size())) == NULL)
+      return NULL;
+
+  // Set the list elements.
+  for (int i = 0; i < sipCpp->size(); ++i)
+  {
+    QPair<TYPE, TYPE>* p = new QPair<TYPE, TYPE>(sipCpp->at(i));
+    PyObject *ptuple = PyTuple_New(2);
+    PyObject *pfirst;
+    PyObject *psecond;
+
+    TYPE *sfirst = new TYPE(p->first);
+    if ((pfirst = sipConvertFromType(sfirst, sipType_TYPE, sipTransferObj)) == NULL)
+    {
+      Py_DECREF(l);
+      Py_DECREF(ptuple);
+      return NULL;
+    }
+    PyTuple_SET_ITEM(ptuple, 0, pfirst);
+
+    TYPE *ssecond = new TYPE(p->second);
+    if ((psecond = sipConvertFromType(ssecond, sipType_TYPE, sipTransferObj)) == NULL)
+    {
+      Py_DECREF(l);
+      Py_DECREF(ptuple);
+      Py_DECREF(pfirst);
+      return NULL;
+    }
+    PyTuple_SET_ITEM(ptuple, 1, psecond);
+
+    PyList_SET_ITEM(l, i, ptuple);
+  }
+
+  return l;
+%End
+
+%ConvertToTypeCode
+  const sipTypeDef* qpair_type = sipFindType("QPair<TYPE, TYPE>");
+
+  // Check the type if that is all that is required.
+  if (sipIsErr == NULL)
+  {
+    if (!PySequence_Check(sipPy))
+      return 0;
+
+    for (int i = 0; i < PySequence_Size(sipPy); ++i)
+      if (!sipCanConvertToType(PySequence_ITEM(sipPy, i), qpair_type, SIP_NOT_NONE))
+        return 0;
+
+    return 1;
+  }
+
+
+  QVector< QPair<TYPE, TYPE> > *qv = new QVector< QPair<TYPE, TYPE> >;
+
+  for (int i = 0; i < PySequence_Size(sipPy); ++i)
+  {
+    int state;
+    QPair<TYPE, TYPE> * p = reinterpret_cast< QPair<TYPE, TYPE> * >(sipConvertToType(PySequence_ITEM(sipPy, i), qpair_type, sipTransferObj, SIP_NOT_NONE, &state, sipIsErr));
+
+    if (*sipIsErr)
+    {
+      sipReleaseType(p, qpair_type, state);
+      delete qv;
+      return 0;
+    }
+    qv->append(*p);
+    sipReleaseType(p, qpair_type, state);
+  }
+
+  *sipCppPtr = qv;
+  return sipGetState(sipTransferObj);
+%End
+
+};
+
 
 /* kate: indent-width 4; space-indent on; hl c++; indent-mode cstyle; */