diff --git a/src/amply/amply.py b/src/amply/amply.py
index 7ebe016..68e2028 100644
--- a/src/amply/amply.py
+++ b/src/amply/amply.py
@@ -610,7 +610,7 @@ def mark_transposed(tokens):
 # What follows is a Pyparsing description of the grammar
 
 index = Word(alphanums, exact=1)
-symbol = Word(alphanums, bodyChars=alphanums + "_", min=1)
+symbol = Word(alphanums + "_", bodyChars=alphanums + "_", min=1)
 sign = Optional(oneOf("+ -"))
 integer = Combine(sign + Word(nums)).setParseAction(lambda t: int(t[0]))
 number = Combine(
diff --git a/tests/test_amply.py b/tests/test_amply.py
index 9c7d9a9..f212298 100644
--- a/tests/test_amply.py
+++ b/tests/test_amply.py
@@ -1,8 +1,8 @@
+import pytest
+
 import unittest
 from io import StringIO
 
-import pytest
-
 from amply import amply
 from amply.amply import (
     number,
@@ -79,7 +79,6 @@ def test_not_symbol(self):
         0.234
         +1e-049
         skj!adfk
-        __12
         """
         result = symbol.runTests(fixture, failureTests=True)
         assert result[0]
@@ -227,7 +226,7 @@ def test_from_file(self):
         try:
             s = StringIO("param T:= 4;")
         except TypeError:
-            s = StringIO(u"param T:= 4;")
+            s = StringIO("param T:= 4;")
         assert amply.Amply.from_file(s).T == 4
 
     def test_load_string(self):
@@ -242,7 +241,7 @@ def test_load_file(self):
         try:
             s = StringIO("param S := 6; param X := 1 2;")
         except TypeError:
-            s = StringIO(u"param S := 6; param X := 1 2;")
+            s = StringIO("param S := 6; param X := 1 2;")
         a.load_file(s)
         assert a.T == 4
         assert a.S == 6