diff -r 1b8b5324506c -r 70c1cc354a8f xmlclass/xsdschema.py
--- a/xmlclass/xsdschema.py	Mon Oct 09 12:30:14 2017 +0300
+++ b/xmlclass/xsdschema.py	Mon Oct 09 16:04:39 2017 +0300
@@ -50,9 +50,10 @@
     return generateXMLTextMethod
 
 
-def GenerateFloatXMLText(extra_values=[], decimal=None):
+def GenerateFloatXMLText(extra_values=None, decimal=None):
     float_format = (lambda x: "{:.{width}f}".format(x, width=decimal).rstrip('0')
                     if decimal is not None else str)
+    extra_values = [] if extra_values is None else extra_values
 
     def generateXMLTextMethod(value, name=None, indent=0):
         text = ""