diff --git a/opytex/opytex.py b/opytex/opytex.py
index 013b430..6e608d1 100755
--- a/opytex/opytex.py
+++ b/opytex/opytex.py
@@ -18,6 +18,8 @@ from pymath.calculus.polynomDeg2 import Polynom_deg2
 from pymath import Fraction 
 from pymath import random_str 
 from pymath import random_pythagore
+from pymath import Dataset
+from pymath import WeightedDataset
 
 
 export_dict = {}
@@ -31,6 +33,8 @@ export_dict.update({"Expression":Expression,\
         "Equation":Equation,\
         "random_str": random_str,\
         "random_pythagore":random_pythagore,\
+        "Dataset": Dataset, \
+        "WeightedDataset": WeightedDataset,\
         })
 
 def produce_and_compile(options):