diff --git a/builtin/builtin.go b/builtin/builtin.go
index e99969c3..b009090a 100644
--- a/builtin/builtin.go
+++ b/builtin/builtin.go
@@ -87,8 +87,8 @@ func init() {
 		"object": py.ObjectType,
 		"range":  py.RangeType,
 		// "reversed":       py.ReversedType,
-		"set": py.SetType,
-		"slice":          py.SliceType,
+		"set":          py.SetType,
+		"slice":        py.SliceType,
 		"staticmethod": py.StaticMethodType,
 		"str":          py.StringType,
 		// "super":          py.SuperType,
diff --git a/coverage.txt b/coverage.txt
new file mode 100644
index 00000000..e69de29b
diff --git a/parser/lexer_test.go b/parser/lexer_test.go
index d8655605..18e20e5a 100644
--- a/parser/lexer_test.go
+++ b/parser/lexer_test.go
@@ -574,7 +574,7 @@ func approxEq(a, b float64) bool {
 	log.Printf("ApproxEq(a = %#v, b = %#v)", a, b)
 	diff := a - b
 	log.Printf("ApproxEq(diff = %e)", diff)
-	if math.Abs(diff) > 1E-10 {
+	if math.Abs(diff) > 1e-10 {
 		log.Printf("ApproxEq(false)")
 		return false
 	}
diff --git a/py/range.go b/py/range.go
index a54005c8..1f0513f8 100644
--- a/py/range.go
+++ b/py/range.go
@@ -226,9 +226,9 @@ func computeRangeSlice(r *Range, s *Slice) (Object, error) {
 	sliceLength = computeRangeLength(startIndex, stopIndex, stepIndex)
 
 	return &Range{
-		Start: startIndex,
-		Stop: stopIndex,
-		Step: stepIndex,
+		Start:  startIndex,
+		Stop:   stopIndex,
+		Step:   stepIndex,
 		Length: sliceLength,
 	}, nil
 }
@@ -238,7 +238,6 @@ var _ I__getitem__ = (*Range)(nil)
 var _ I__iter__ = (*Range)(nil)
 var _ I_iterator = (*RangeIterator)(nil)
 
-
 func (a *Range) M__eq__(other Object) (Object, error) {
 	b, ok := other.(*Range)
 	if !ok {
diff --git a/py/range_repr110.go b/py/range_repr110.go
index 2db201d2..dfe4ee8c 100644
--- a/py/range_repr110.go
+++ b/py/range_repr110.go
@@ -35,4 +35,4 @@ func (r *Range) repr() (Object, error) {
 	b.WriteString(")")
 
 	return String(b.String()), nil
-}
\ No newline at end of file
+}
diff --git a/py/range_repr19.go b/py/range_repr19.go
index ff527aa6..0fd8b791 100644
--- a/py/range_repr19.go
+++ b/py/range_repr19.go
@@ -35,4 +35,4 @@ func (r *Range) repr() (Object, error) {
 	b.WriteString(")")
 
 	return String(b.String()), nil
-}
\ No newline at end of file
+}
diff --git a/py/set.go b/py/set.go
index 171900b3..b1b74e26 100644
--- a/py/set.go
+++ b/py/set.go
@@ -8,6 +8,8 @@
 
 package py
 
+import "bytes"
+
 var SetType = NewTypeX("set", "set() -> new empty set object\nset(iterable) -> new set object\n\nBuild an unordered collection of unique elements.", SetNew, nil)
 
 type SetValue struct{}
@@ -102,6 +104,25 @@ func (s *Set) M__bool__() (Object, error) {
 	return NewBool(len(s.items) > 0), nil
 }
 
+func (s *Set) M__repr__() (Object, error) {
+	var out bytes.Buffer
+	out.WriteRune('{')
+	spacer := false
+	for item := range s.items {
+		if spacer {
+			out.WriteString(", ")
+		}
+		str, err := ReprAsString(item)
+		if err != nil {
+			return nil, err
+		}
+		out.WriteString(str)
+		spacer = true
+	}
+	out.WriteRune('}')
+	return String(out.String()), nil
+}
+
 func (s *Set) M__iter__() (Object, error) {
 	items := make(Tuple, 0, len(s.items))
 	for item := range s.items {
diff --git a/py/tests/set.py b/py/tests/set.py
index e7023495..834e457b 100644
--- a/py/tests/set.py
+++ b/py/tests/set.py
@@ -56,6 +56,15 @@
 d = a ^ b
 assert 1 in c
 
+doc="__repr__"
+a = {1, 2, 3}
+b = a.__repr__()
+assert "{" in b
+assert "1" in b
+assert "2" in b
+assert "3" in b
+assert "}" in b
+
 doc="set"
 a = set([1,2,3])
 b = set("set")
@@ -83,4 +92,4 @@
 assert a.__eq__({1,2,3}) == True
 assert a.__ne__({1,2,3}) == False
 
-doc="finished"
\ No newline at end of file
+doc="finished"
diff --git a/symtable/symtable_data_test.go b/symtable/symtable_data_test.go
index 05ec1da6..b755841d 100644
--- a/symtable/symtable_data_test.go
+++ b/symtable/symtable_data_test.go
@@ -514,7 +514,7 @@ var symtableTestData = []struct {
 				Children: Children{},
 			},
 		},
-	}, nil,""},
+	}, nil, ""},
 	{"def fn(a):\n    global b\n    global b\n    return b", "exec", &SymTable{
 		Type:              ModuleBlock,
 		Name:              "top",
diff --git a/time/time.go b/time/time.go
index 84eb8288..88deb94a 100644
--- a/time/time.go
+++ b/time/time.go
@@ -18,7 +18,7 @@ Return the current time in seconds since the Epoch.
 Fractions of a second may be present if the system clock provides them.`
 
 func time_time(self py.Object) (py.Object, error) {
-	return py.Float(time.Now().UnixNano()) / 1E9, nil
+	return py.Float(time.Now().UnixNano()) / 1e9, nil
 }
 
 // func floatclock(_Py_clock_info_t *info) (py.Object, error) {
@@ -141,7 +141,7 @@ func time_sleep(self py.Object, args py.Tuple) (py.Object, error) {
 	if secs < 0 {
 		return nil, py.ExceptionNewf(py.ValueError, "sleep length must be non-negative")
 	}
-	time.Sleep(time.Duration(secs * 1E9))
+	time.Sleep(time.Duration(secs * 1e9))
 	return py.None, nil
 }