fixup! fix SyntaxWarning

product/ERP5Type/Base.py

@@ -1014,10 +1014,10 @@ class Base(
               result = None
             else:
               if isinstance(value, (list, tuple)):
-                if len(value) is 0:
-                  result = None
-                else:
+                if len(value):
                   result = value[0]
+                else:
+                  result = None
               else:
                 result = value
           else:
@@ -1048,10 +1048,10 @@ class Base(
             result = None
           else:
             if isinstance(value, (list, tuple)):
-              if len(value) is 0:
-                result = None
-              else:
+              if len(value):
                 result = value[0]
+              else:
+                result = None
             else:
               result = value
         else:
@@ -1092,10 +1092,10 @@ class Base(
             result = None
           else:
             if isinstance(value, (list, tuple)):
-              if len(value) is 0:
-                result = None
-              else:
+              if len(value):
                 result = value[0]
+              else:
+                result = None
             else:
               result = value
         else:

product/ERP5Type/XMLExportImport/ppml.py

@@ -900,7 +900,7 @@ def save_bytes(self, tag, data):
     v = b''.join(data[2:])
     encoding = a.get('encoding', 'repr')
     assert encoding == 'base64'
-    if encoding is not '':
+    if encoding != '':
         v = unconvert(encoding, v)
     if self.binary:
         l = len(v)
@@ -924,7 +924,7 @@ def save_unicode(self, tag, data):
         for x in data[2:]:
             v=v+x
     encoding=a.get('encoding','repr') # JPS: repr is default encoding
-    if encoding is not '':
+    if encoding != '':
         v=unconvert(encoding,v)
     if binary:
         l=len(v)