added simplified declaration for sum_of_simplified_exponential_functions

src/main/py/read_math_function.py

@@ -113,4 +113,5 @@ def simplify_product_function(type, function):
 def sum_of_simplified_exponential_functions(type, function):
     if type !="se":
         return False
-    summands = function.split('+')
+    summands = function.split('+')
+    simplified = simplify_exponential_function('e', summands)