Properly close opened files in two tests

Author: agraboso

pandas/io/tests/sas/test_sas7bdat.py

@@ -44,7 +44,8 @@ def test_from_buffer(self):
             df0 = self.data[j]
             for k in self.test_ix[j]:
                 fname = os.path.join(self.dirpath, "test%d.sas7bdat" % k)
-                byts = open(fname, 'rb').read()
+                with open(fname, 'rb') as f:
+                    byts = f.read()
                 buf = io.BytesIO(byts)
                 df = pd.read_sas(buf, format="sas7bdat", encoding='utf-8')
                 tm.assert_frame_equal(df, df0, check_exact=False)
@@ -54,7 +55,8 @@ def test_from_iterator(self):
             df0 = self.data[j]
             for k in self.test_ix[j]:
                 fname = os.path.join(self.dirpath, "test%d.sas7bdat" % k)
-                byts = open(fname, 'rb').read()
+                with open(fname, 'rb') as f:
+                    byts = f.read()
                 buf = io.BytesIO(byts)
                 rdr = pd.read_sas(buf, format="sas7bdat",
                                   iterator=True, encoding='utf-8')