diff --git a/sepaxml/debit.py b/sepaxml/debit.py
index 0950643..ba823c6 100644
--- a/sepaxml/debit.py
+++ b/sepaxml/debit.py
@@ -323,7 +323,7 @@ def _add_non_batch(self, TX_nodes, PmtInf_nodes):
         PmtInf_nodes['PmtInfNode'].append(PmtInf_nodes['ReqdColltnDtNode'])
 
         PmtInf_nodes['CdtrNode'].append(PmtInf_nodes['Nm_Cdtr_Node'])
-        if PmtInf_nodes['PstlAdr_Cdtr_Node']:
+        if len(PmtInf_nodes['PstlAdr_Cdtr_Node']):
             PmtInf_nodes['CdtrNode'].append(PmtInf_nodes['PstlAdr_Cdtr_Node'])
         PmtInf_nodes['PmtInfNode'].append(PmtInf_nodes['CdtrNode'])
 
@@ -378,7 +378,7 @@ def _add_non_batch(self, TX_nodes, PmtInf_nodes):
         TX_nodes['DrctDbtTxInfNode'].append(TX_nodes['DbtrAgtNode'])
 
         TX_nodes['DbtrNode'].append(TX_nodes['Nm_Dbtr_Node'])
-        if TX_nodes['PstlAdr_Dbtr_Node']:
+        if len(TX_nodes['PstlAdr_Dbtr_Node']):
             TX_nodes['DbtrNode'].append(TX_nodes['PstlAdr_Dbtr_Node'])
         TX_nodes['DrctDbtTxInfNode'].append(TX_nodes['DbtrNode'])
 
@@ -420,7 +420,7 @@ def _add_batch(self, TX_nodes, payment):
         TX_nodes['DrctDbtTxInfNode'].append(TX_nodes['DbtrAgtNode'])
 
         TX_nodes['DbtrNode'].append(TX_nodes['Nm_Dbtr_Node'])
-        if TX_nodes['PstlAdr_Dbtr_Node']:
+        if len(TX_nodes['PstlAdr_Dbtr_Node']):
             TX_nodes['DbtrNode'].append(TX_nodes['PstlAdr_Dbtr_Node'])
         TX_nodes['DrctDbtTxInfNode'].append(TX_nodes['DbtrNode'])
 
@@ -520,7 +520,7 @@ def _finalize_batch(self):
             PmtInf_nodes['PmtInfNode'].append(PmtInf_nodes['ReqdColltnDtNode'])
 
             PmtInf_nodes['CdtrNode'].append(PmtInf_nodes['Nm_Cdtr_Node'])
-            if PmtInf_nodes['PstlAdr_Cdtr_Node']:
+            if len(PmtInf_nodes['PstlAdr_Cdtr_Node']):
                 PmtInf_nodes['CdtrNode'].append(PmtInf_nodes['PstlAdr_Cdtr_Node'])
             PmtInf_nodes['PmtInfNode'].append(PmtInf_nodes['CdtrNode'])
 
diff --git a/tests/transfer/test_config.py b/tests/transfer/test_config.py
index 1f157eb..ab6c22b 100644
--- a/tests/transfer/test_config.py
+++ b/tests/transfer/test_config.py
@@ -4,7 +4,7 @@
 
 
 def test_valid_config():
-    return SepaTransfer({
+    SepaTransfer({
         "name": "TestCreditor",
         "IBAN": "NL50BANK1234567890",
         "BIC": "BANKNL2A",
@@ -15,7 +15,7 @@ def test_valid_config():
 
 def test_invalid_config():
     with pytest.raises(Exception):
-        return SepaTransfer({
+        SepaTransfer({
             "name": "TestCreditor",
             "BIC": "BANKNL2A",
             "batch": True,