adding class MathicsSession

Author: mmatera

mathics/session.py

@@ -0,0 +1,19 @@
+from mathics.core.parser import parse, SingleLineFeeder
+from mathics.core.definitions import Definitions
+from mathics.core.evaluation import Evaluation
+from mathics import settings
+
+
+class MathicsSession:
+    def __init__(self, add_builtin=True, catch_interrupt=False, form="InputForm"):
+        self.definitions = Definitions(add_builtin)
+        self.evaluation = Evaluation(definitions=self.definitions, catch_interrupt=catch_interrupt)
+        self.form = form
+        
+    def evaluate(self, str_expression, timeout = None, form= None):
+        expr = parse(self.definitions, SingleLineFeeder(str_expression))
+        if form is None:
+            form = self.form
+        return expr.evaluate(self.evaluation).format(ms.evaluation, form)
+
+