Fix a few pylint warnings

taxcalc/calculator.py

@@ -1044,12 +1044,14 @@ def pch_graph(self, calc, pop_quantiles=False):
         data = pch_graph_data(vdf, year=self.current_year,
                               pop_quantiles=pop_quantiles)
         # construct figure from data
-        fig = pch_graph_plot(data,
-                             width=850,
-                             height=500,
-                             xlabel='',
-                             ylabel='',
-                             title='')
+        # (see comment at end of pch_graph_plot function in utils.py)
+        fig = pch_graph_plot(  # pylint: disable=assignment-from-no-return
+            data,
+            width=850,
+            height=500,
+            xlabel='',
+            ylabel='',
+            title='')
         return fig
 
     REQUIRED_REFORM_KEYS = set(['policy'])

taxcalc/tests/test_decorators.py

@@ -133,9 +133,14 @@ def magic_calc2(x, y, z):
     return (a, b)
 
 
-class Foo:
+class Foo:  # pylint: disable=too-many-instance-attributes
     """Foo class"""
-    # pylint: disable=too-few-public-methods,too-many-instance-attributes
+
+    def faux_method1(self):
+        """ Foo method"""
+
+    def faux_method2(self):
+        """ Foo method"""
 
 
 @iterate_jit(nopython=True)

taxcalc/utils.py

@@ -1314,10 +1314,10 @@ def pch_graph_plot(data,
     # bokeh cannot save this fig saying:
     #   bokeh.core.serialization.SerializationError:
     #   can't serialize <class 'range'>
-    # so the "return fig" statement is replaced by "return None" until
-    # the above logic can be made compatible with modern bokeh packages
+    # so the "return fig" statement is replaced by Python's implicit
+    # "return None" until the above logic can be made compatible with
+    # modern bokeh packages
     # return fig
-    return None
 
 
 def write_graph_file(figure, filename, title):