diff --git a/pymath/expression.py b/pymath/expression.py
index 539082d..7318827 100644
--- a/pymath/expression.py
+++ b/pymath/expression.py
@@ -395,10 +395,10 @@ if __name__ == '__main__':
     #exp="-2*4(12 + 1)(3-12)"
     #test(exp)
 
-    #exp="-2+a+(12 + 1)(3-12) : 34a"
-    ##test(exp)
-    #e = Expression(exp)
-    #print(e.render(render = tex_render))
+    exp="-2+a+(12 + 1)(3-12) / 34a"
+    #test(exp)
+    e = Expression(exp)
+    print(e.render(render = tex_render))
 
     #exp="-2*b+a(12 + 1)(3-12)"
     #test(exp)
diff --git a/renders.py b/pymath/renders.py
similarity index 94%
rename from renders.py
rename to pymath/renders.py
index be25d01..f213e17 100644
--- a/renders.py
+++ b/pymath/renders.py
@@ -1,10 +1,10 @@
 #!/usr/bin/env python
 # encoding: utf-8
 
-from render import Render
-from fraction import Fraction
-from formal import FormalExp
-from generic import first_elem
+from .render import Render
+from .fraction import Fraction
+from .formal import FormalExp
+from .generic import first_elem
 
 # ------------------------
 # A console render