diff --git a/include/pybind11/functional.h b/include/pybind11/functional.h
index 8a8c32c0ec..0107c67fb0 100644
--- a/include/pybind11/functional.h
+++ b/include/pybind11/functional.h
@@ -14,6 +14,7 @@
 #include "pybind11.h"
 
 #include <functional>
+#include <iostream>
 
 PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
 PYBIND11_NAMESPACE_BEGIN(detail)
@@ -129,7 +130,7 @@ struct type_caster<std::function<Return(Args...)>> {
             // See PR #1413 for full details
         } else {
             // Check number of arguments of Python function
-            auto argCountFromFuncCode = [&](handle &obj) {
+            auto argCountFromFuncCode = [](handle &obj) {
                 // This is faster then doing import inspect and
                 // inspect.signature(obj).parameters
 
@@ -138,20 +139,40 @@ struct type_caster<std::function<Return(Args...)>> {
             };
             size_t argCount = 0;
 
-            handle codeAttr = PyObject_GetAttrString(src.ptr(), "__code__");
-            if (codeAttr) {
+            std::cout << "BEFORE " << std::endl;
+            auto codeAttr
+                = reinterpret_borrow<object> (PyObject_GetAttrString(src.ptr(), "__code__"));
+            assert(((codeAttr)
+                       == static_cast<bool>(PyObject_HasAttrString(src.ptr(), "__code__")))
+                   && "ptr and "
+                      "HasAttrString "
+                      "inconsistent for __code__");
+            if (static_cast<bool>(PyObject_HasAttrString(src.ptr(), "__code__"))) {
+                std::cout << "__code__ exists" << std::endl;
                 argCount = argCountFromFuncCode(codeAttr);
             } else {
-                handle callAttr = PyObject_GetAttrString(src.ptr(), "__call__");
-                if (callAttr) {
-                    handle codeAttr2 = PyObject_GetAttrString(callAttr.ptr(), "__code__");
+                auto callAttr
+                    = reinterpret_borrow<object> (PyObject_GetAttrString(src.ptr(), "__call__"));
+                assert(
+                    ((callAttr)
+                    == static_cast<bool>(PyObject_HasAttrString(src.ptr(), "__call__"))) && "ptr and "
+                      "HasAttrString "
+                      "inconsistent for __call__");
+                if (callAttr.ptr()!=nullptr) {
+                    std::cout << "__call__ exists" << std::endl;
+                    auto codeAttr2 = reinterpret_borrow<object> (PyObject_GetAttrString(
+                        callAttr.ptr(), "__code__"));
                     argCount = argCountFromFuncCode(codeAttr2)
                                - 1; // we have to remove the self argument
                 } else {
                     // No __code__ or __call__ attribute, this is not a proper Python function
+                    std::cout << "No __code__ or __call__ attribute, this is not a proper Python "
+                                 "function"
+                              << std::endl;
                     return false;
                 }
             }
+            std::cout << "AFTER " << std::endl;
             // if we are a method, we have to correct the argument count since we are not counting
             // the self argument
             const size_t self_offset = static_cast<bool>(PyMethod_Check(src.ptr())) ? 1 : 0;