Fix pylint W1514 and W3301 warnings

taxcalc/calcfunctions.py

@@ -2310,7 +2310,7 @@ def F2441(MARS, earned_p, earned_s, f2441, CDCC_c, e32800,
         c32890 = earned_s  # earned income of spouse when present
     else:
         c32890 = earned_p
-    c33000 = max(0., min(c32800, min(c32880, c32890)))
+    c33000 = max(0., min(c32800, c32880, c32890))
     # credit rate is limited at high AGI
     # ... first phase-down from CDCC_crt to CDCC_frt
     steps_fractional = max(0., c00100 - CDCC_ps) / CDCC_po_step_size

taxcalc/tests/conftest.py

@@ -88,7 +88,7 @@ def fixture_test_reforms(tests_path):
         for afile in glob.glob(afiles):
             os.remove(afile)
         # create reforms_actual_init file
-        with open(initfile, 'w') as ifile:
+        with open(initfile, 'w', encoding='utf-8') as ifile:
             ifile.write('test_reforms initialization done')
     else:
         num_waits = 0
@@ -109,7 +109,7 @@ def fixture_test_reforms(tests_path):
         # compare actual and expected results for each test
         # ... read expected results
         efile_path = os.path.join(tests_path, 'reforms_expect.csv')
-        with open(efile_path, 'r') as efile:
+        with open(efile_path, 'r', encoding='utf-8') as efile:
             expect_lines = efile.readlines()
         # ... compare actual and expected results for each test
         diffs = False

taxcalc/tests/test_growdiff.py

@@ -63,7 +63,7 @@ def test_description_punctuation(tests_path):
     """
     # read JSON file into a dictionary
     path = os.path.join(tests_path, '..', 'growdiff.json')
-    with open(path, 'r') as jsonfile:
+    with open(path, 'r', encoding='utf-8') as jsonfile:
         dct = json.load(jsonfile)
     all_desc_ok = True
     for param in dct.keys():
@@ -83,7 +83,7 @@ def test_boolean_value_infomation(tests_path):
     """
     # read growdiff.json file into a dictionary
     path = os.path.join(tests_path, '..', 'growdiff.json')
-    with open(path, 'r') as gddfile:
+    with open(path, 'r', encoding='utf-8') as gddfile:
         gdd = json.load(gddfile)
     for param in gdd.keys():
         if param == "schema":