Fix pylint R1710 and R1711 warnings

taxcalc/parameters.py

@@ -2,11 +2,9 @@
 import copy
 from collections import defaultdict
 from typing import Union, Mapping, Any, List
-
+import numpy as np
 import marshmallow as ma
 import paramtools as pt
-import numpy as np
-
 from taxcalc.growfactors import GrowFactors
 
 
@@ -515,7 +513,8 @@ def inflation_rates(self, year=None):
             return self._inflation_rates[year - syr]
         return self._inflation_rates or []
 
-    # alias methods below
+    # alias methods below:
+
     def initialize(self, start_year, num_years, last_known_year=None,
                    removed=None, redefined=None, wage_indexed=None,
                    **kwargs):
@@ -530,6 +529,7 @@ def initialize(self, start_year, num_years, last_known_year=None,
                 removed=removed, redefined=redefined,
                 wage_indexed=wage_indexed, **kwargs
             )
+        return None
 
     def _update(self, revision, print_warnings, raise_errors):
         """

taxcalc/utils.py

@@ -1310,7 +1310,6 @@ def pch_graph_plot(data,
     fig.yaxis.axis_label_text_font_style = 'normal'
     fig.yaxis[0].formatter = PrintfTickFormatter(format='%.1f')
     # return fig  # bokeh 3.4.1 cannot save this figure for some unknown reason
-    return None
 
 
 def write_graph_file(figure, filename, title):