diff --git a/mapytex/calculus/core/typing/__init__.py b/mapytex/calculus/core/typing/__init__.py
index 057577b..045de4f 100644
--- a/mapytex/calculus/core/typing/__init__.py
+++ b/mapytex/calculus/core/typing/__init__.py
@@ -28,7 +28,7 @@ from tabulate import tabulate
 MOS = [ MOnumber, MOstr, MOFraction, MOstrPower, MOMonomial, MOpolynomial]
 
 OPERATIONS = {
-        "+": add, 
+        "+": add,
         # "-": minus, 
         "*": multiply,
         "/": divide,
@@ -37,7 +37,7 @@ OPERATIONS = {
 
 def typing(node, left_v, right_v,\
            raiseTypingError = True):
-    """ 
+    """
     Typing a try base on his root node
 
     """
@@ -48,7 +48,7 @@ def typing(node, left_v, right_v,\
     return operation(left_v, right_v)
 
 def typing_capacities(node):
-    """ Test an operation through all MOs 
+    """ Test an operation through all MOs
 
     :param operation: string which represent an (mo, mo) -> mo
     :returns: { (motype, motype): True/False } when it's implemented