diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 52849c8d..367facec 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
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+      <change type="MODIFICATION" beforePath="$PROJECT_DIR$/tests/test-models/tests/number_handling/test_number_handling.py" afterPath="$PROJECT_DIR$/tests/test-models/tests/number_handling/test_number_handling.py" />
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     </entry>
@@ -1463,22 +1461,6 @@
         </state>
       </provider>
     </entry>
-    <entry file="file://$PROJECT_DIR$/.travis.yml">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="195">
-          <caret line="13" column="7" selection-start-line="13" selection-start-column="7" selection-end-line="13" selection-end-column="7" />
-          <folding />
-        </state>
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/tests/unit_test_pysd.py">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="150">
-          <caret line="24" column="23" selection-start-line="24" selection-start-column="23" selection-end-line="24" selection-end-column="23" />
-          <folding />
-        </state>
-      </provider>
-    </entry>
     <entry file="file://$USER_HOME$/anaconda/envs/py3k/lib/python3.5/unittest/case.py">
       <provider selected="true" editor-type-id="text-editor">
         <state relative-caret-position="12090">
@@ -1537,18 +1519,34 @@
         </state>
       </provider>
     </entry>
+    <entry file="file://$PROJECT_DIR$/pysd/builder.py">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="3900">
+          <caret line="265" column="20" selection-start-line="265" selection-start-column="20" selection-end-line="265" selection-end-column="20" />
+          <folding />
+        </state>
+      </provider>
+    </entry>
     <entry file="file://$PROJECT_DIR$/pysd/pysd.py">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="-17">
+        <state relative-caret-position="15">
           <caret line="428" column="11" selection-start-line="428" selection-start-column="11" selection-end-line="428" selection-end-column="11" />
           <folding />
         </state>
       </provider>
     </entry>
-    <entry file="file://$PROJECT_DIR$/pysd/builder.py">
+    <entry file="file://$PROJECT_DIR$/tests/unit_test_pysd.py">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="-782">
-          <caret line="265" column="20" selection-start-line="265" selection-start-column="20" selection-end-line="265" selection-end-column="20" />
+        <state relative-caret-position="150">
+          <caret line="24" column="23" selection-start-line="24" selection-start-column="23" selection-end-line="24" selection-end-column="23" />
+          <folding />
+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/.travis.yml">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="195">
+          <caret line="13" column="7" selection-start-line="13" selection-start-column="7" selection-end-line="13" selection-end-column="7" />
           <folding />
         </state>
       </provider>
diff --git a/pysd/pysd.py b/pysd/pysd.py
index b844ecd4..a136d9e8 100644
--- a/pysd/pysd.py
+++ b/pysd/pysd.py
@@ -103,11 +103,11 @@ def __str__(self):
         # JT: Might be helpful to return not only the source file, but
         # also how the instance differs from that source file. This
         # would give a more accurate view of the current model.
-        str = 'Translated Model File: ' + self.py_model_file
+        string = 'Translated Model File: ' + self.py_model_file
         if hasattr(self, 'mdl_file'):
-            str += '\n Original Model File: ' + self.mdl_file
+            string += '\n Original Model File: ' + self.mdl_file
 
-        return str
+        return string
 
     def run(self, params=None, return_columns=None, return_timestamps=None,
             initial_condition='original'):
diff --git a/tests/test-models b/tests/test-models
index 8c5ebba7..bf939db2 160000
--- a/tests/test-models
+++ b/tests/test-models
@@ -1 +1 @@
-Subproject commit 8c5ebba76b829bd130e4e38977ff40fb435235ae
+Subproject commit bf939db2d20f9583b1bea1ea4c77e98679ef0953