applied 2to3 + some manual fixes.

.travis.yml

@@ -1,7 +1,8 @@
 language: python
 
 python:
-  - "2.7"
+  - 3.6
+  - latest
 
 virtualenv:
   system_site_packages: true

quantulum/classes.py

@@ -1,95 +1,95 @@
-#!/usr/bin/env python
-# -*- coding: utf-8 -*-
-
-"""quantulum classes."""
-
-
-###############################################################################
-class Quantity(object):
-    """Class for a quantity (e.g. "4.2 gallons")."""
-
-    def __init__(self, value=None, unit=None, surface=None, span=None,
-                 uncertainty=None):
-        """Initialization method."""
-        self.value = value
-        self.unit = unit
-        self.surface = surface
-        self.span = span
-        self.uncertainty = uncertainty
-
-    def __repr__(self):
-        """Representation method."""
-        msg = u'Quantity(%g, "%s")'
-        msg = msg % (self.value, self.unit.name)
-        return msg.encode('utf-8')
-
-    def __eq__(self, other):
-        """Equality method."""
-        if isinstance(other, self.__class__):
-            return self.__dict__ == other.__dict__
-        else:
-            return False
-
-    def __ne__(self, other):
-        """Non equality method."""
-        return not self.__eq__(other)
-
-
-###############################################################################
-class Unit(object):
-    """Class for a unit (e.g. "gallon")."""
-
-    def __init__(self, name=None, surfaces=None, entity=None, uri=None,
-                 symbols=None, dimensions=None):
-        """Initialization method."""
-        self.name = name
-        self.surfaces = surfaces
-        self.entity = entity
-        self.uri = uri
-        self.symbols = symbols
-        self.dimensions = dimensions
-
-    def __repr__(self):
-        """Representation method."""
-        msg = u'Unit(name="%s", entity=Entity("%s"), uri=%s)'
-        msg = msg % (self.name, self.entity.name, self.uri)
-        return msg.encode('utf-8')
-
-    def __eq__(self, other):
-        """Equality method."""
-        if isinstance(other, self.__class__):
-            return self.__dict__ == other.__dict__
-        else:
-            return False
-
-    def __ne__(self, other):
-        """Non equality method."""
-        return not self.__eq__(other)
-
-
-###############################################################################
-class Entity(object):
-    """Class for an entity (e.g. "volume")."""
-
-    def __init__(self, name=None, dimensions=None, uri=None):
-        """Initialization method."""
-        self.name = name
-        self.dimensions = dimensions
-        self.uri = uri
-
-    def __repr__(self):
-        """Representation method."""
-        msg = u'Entity(name="%s", uri=%s)'
-        msg = msg % (self.name, self.uri)
-        return msg.encode('utf-8')
-
-    def __eq__(self, other):
-        """Equality method."""
-        if isinstance(other, self.__class__):
-            return self.__dict__ == other.__dict__
-        else:
-            return False
-
-    def __ne__(self, other):
-        """Non equality method."""
-        return not self.__eq__(other)
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""quantulum classes."""
+
+
+###############################################################################
+class Quantity(object):
+    """Class for a quantity (e.g. "4.2 gallons")."""
+
+    def __init__(self, value=None, unit=None, surface=None, span=None,
+                 uncertainty=None):
+        """Initialization method."""
+        self.value = value
+        self.unit = unit
+        self.surface = surface
+        self.span = span
+        self.uncertainty = uncertainty
+
+    def __repr__(self):
+        """Representation method."""
+        msg = 'Quantity(%g, "%s")'
+        msg = msg % (self.value, self.unit.name)
+        return msg
+
+    def __eq__(self, other):
+        """Equality method."""
+        if isinstance(other, self.__class__):
+            return self.__dict__ == other.__dict__
+        else:
+            return False
+
+    def __ne__(self, other):
+        """Non equality method."""
+        return not self.__eq__(other)
+
+
+###############################################################################
+class Unit(object):
+    """Class for a unit (e.g. "gallon")."""
+
+    def __init__(self, name=None, surfaces=None, entity=None, uri=None,
+                 symbols=None, dimensions=None):
+        """Initialization method."""
+        self.name = name
+        self.surfaces = surfaces
+        self.entity = entity
+        self.uri = uri
+        self.symbols = symbols
+        self.dimensions = dimensions
+
+    def __repr__(self):
+        """Representation method."""
+        msg = 'Unit(name="%s", entity=Entity("%s"), uri=%s)'
+        msg = msg % (self.name, self.entity.name, self.uri)
+        return msg
+
+    def __eq__(self, other):
+        """Equality method."""
+        if isinstance(other, self.__class__):
+            return self.__dict__ == other.__dict__
+        else:
+            return False
+
+    def __ne__(self, other):
+        """Non equality method."""
+        return not self.__eq__(other)
+
+
+###############################################################################
+class Entity(object):
+    """Class for an entity (e.g. "volume")."""
+
+    def __init__(self, name=None, dimensions=None, uri=None):
+        """Initialization method."""
+        self.name = name
+        self.dimensions = dimensions
+        self.uri = uri
+
+    def __repr__(self):
+        """Representation method."""
+        msg = 'Entity(name="%s", uri=%s)'
+        msg = msg % (self.name, self.uri)
+        return msg
+
+    def __eq__(self, other):
+        """Equality method."""
+        if isinstance(other, self.__class__):
+            return self.__dict__ == other.__dict__
+        else:
+            return False
+
+    def __ne__(self, other):
+        """Non equality method."""
+        return not self.__eq__(other)