diff --git a/source/app/controllers/utils.py b/source/app/controllers/utils.py
index 73f2651..38c196a 100644
--- a/source/app/controllers/utils.py
+++ b/source/app/controllers/utils.py
@@ -841,9 +841,9 @@ def make_xml(data, certificado):
 def get_pac_by_rfc(cfdi):
     tree = ET.fromstring(cfdi.encode())
     version = tree.attrib['Version']
-    NAME_SPACES = {'cfdi': PRE[version][1:-1], 'tdf': PRE['TIMBRE'][1:-1]}
+    namespaces = {'cfdi': PRE[version][1:-1], 'tdf': PRE['TIMBRE'][1:-1]}
     path = 'string(//cfdi:Complemento/tdf:TimbreFiscalDigital/@RfcProvCertif)'
-    rfc_pac = tree.xpath(path, namespaces=NAME_SPACES)
+    rfc_pac = tree.xpath(path, namespaces=namespaces)
     return RFCS[rfc_pac]
 
 
@@ -909,17 +909,20 @@ def cancel_xml_sign(invoice, args, auth, certificado):
 
 def _get_data_sat(xml):
     BF = 'string(//*[local-name()="{}"]/@{})'
-    NS_CFDI = {'cfdi': 'http://www.sat.gob.mx/cfd/3'}
+    # ~ NS_CFDI = {'cfdi': 'http://www.sat.gob.mx/cfd/3'}
 
     try:
         tree = ET.fromstring(xml.encode())
+        version = tree.attrib['Version']
+        namespaces = {'cfdi': PRE[version][1:-1]}
+
         emisor = escape(
-            tree.xpath('string(//cfdi:Emisor/@rfc)', namespaces=NS_CFDI) or
-            tree.xpath('string(//cfdi:Emisor/@Rfc)', namespaces=NS_CFDI)
+            tree.xpath('string(//cfdi:Emisor/@rfc)', namespaces=namespaces) or
+            tree.xpath('string(//cfdi:Emisor/@Rfc)', namespaces=namespaces)
         )
         receptor = escape(
-            tree.xpath('string(//cfdi:Receptor/@rfc)', namespaces=NS_CFDI) or
-            tree.xpath('string(//cfdi:Receptor/@Rfc)', namespaces=NS_CFDI)
+            tree.xpath('string(//cfdi:Receptor/@rfc)', namespaces=namespaces) or
+            tree.xpath('string(//cfdi:Receptor/@Rfc)', namespaces=namespaces)
         )
         total = tree.get('total') or tree.get('Total')
         uuid = tree.xpath(BF.format('TimbreFiscalDigital', 'UUID'))