diff --git a/doc/conf.py b/doc/conf.py
index ef6f7ab..d3c5d1b 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -1,9 +1,9 @@
 # pylint: disable=invalid-name
 """Sphinx configuration."""
-from datetime import datetime
 import io
 import os
 import re
+from datetime import datetime
 
 VERSION_RE = re.compile(r"""__version__ = ['"]([0-9.]+)['"]""")
 HERE = os.path.abspath(os.path.dirname(__file__))
diff --git a/src/base64io/__init__.py b/src/base64io/__init__.py
index d399080..4822523 100644
--- a/src/base64io/__init__.py
+++ b/src/base64io/__init__.py
@@ -227,7 +227,7 @@ class Base64IO(io.IOBase):
             return data
 
         _data_buffer = io.BytesIO() if isinstance(data, bytes) else io.StringIO()
-        join_char = b'' if isinstance(data, bytes) else u''
+        join_char = b"" if isinstance(data, bytes) else u""
         _data_buffer.write(join_char.join(data.split()))  # type: ignore
         _remaining_bytes_to_read = total_bytes_to_read - _data_buffer.tell()  # type: ignore
 
@@ -274,8 +274,9 @@ class Base64IO(io.IOBase):
         data = self.__wrapped.read(_bytes_to_read)
         # Remove whitespace from read data and attempt to read more data to get the desired
         # number of bytes.
-        whitespace = string.whitespace.encode("utf-8") if isinstance(data, bytes) \
-            else string.whitespace  # type: Union[bytes, str]
+        whitespace = (
+            string.whitespace.encode("utf-8") if isinstance(data, bytes) else string.whitespace
+        )  # type: Union[bytes, str]
 
         if any([char in data for char in whitespace]):
             data = self._read_additional_data_removing_whitespace(data, _bytes_to_read)
diff --git a/test/unit/test_base64_stream.py b/test/unit/test_base64_stream.py
index 4492516..59fe701 100644
--- a/test/unit/test_base64_stream.py
+++ b/test/unit/test_base64_stream.py
@@ -19,8 +19,8 @@ import io
 import math
 import os
 
-from mock import MagicMock, sentinel
 import pytest
+from mock import MagicMock, sentinel
 
 from base64io import Base64IO
 
@@ -159,7 +159,7 @@ def test_base64io_decode(bytes_to_generate, bytes_per_round, number_of_rounds, t
 )
 def test_base64io_decode_str(bytes_to_generate, bytes_per_round, number_of_rounds, total_bytes_to_expect):
     plaintext_source = os.urandom(bytes_to_generate)
-    plaintext_b64 = io.StringIO(base64.b64encode(plaintext_source).decode('ascii'))
+    plaintext_b64 = io.StringIO(base64.b64encode(plaintext_source).decode("ascii"))
     plaintext_wrapped = Base64IO(plaintext_b64)
 
     test = b""
@@ -315,7 +315,7 @@ def test_base64io_decode_with_whitespace(plaintext_source, b64_plaintext_with_wh
 
 @pytest.mark.parametrize("plaintext_source, b64_plaintext_with_whitespace, read_bytes", build_whitespace_testcases())
 def test_base64io_decode_with_whitespace_str(plaintext_source, b64_plaintext_with_whitespace, read_bytes):
-    with Base64IO(io.StringIO(b64_plaintext_with_whitespace.decode('ascii'))) as decoder:
+    with Base64IO(io.StringIO(b64_plaintext_with_whitespace.decode("ascii"))) as decoder:
         test = decoder.read(read_bytes)
 
     assert test == plaintext_source[:read_bytes]
diff --git a/test/unit/test_base64io.py b/test/unit/test_base64io.py
index dfb9d20..07528b7 100644
--- a/test/unit/test_base64io.py
+++ b/test/unit/test_base64io.py
@@ -32,7 +32,7 @@ def test_file():
     if is_python2:
         # If we are in Python 2, the "file" assignment should not
         # happen because it is a builtin object.
-        assert not hasattr(base64io, 'file')
+        assert not hasattr(base64io, "file")
     else:
         # If we are in Python 3, the "file" assignment should happen
         # to provide a concrete definition of the "file" name.