diff --git a/docs/conf.py b/docs/conf.py
index 5157e926..7aa150c7 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -15,46 +15,46 @@
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
-#sys.path.insert(0, os.path.abspath('.'))
+# sys.path.insert(0, os.path.abspath('.'))
 
 import os
 
-DIR = os.path.dirname('__file__')
-with open (os.path.join(DIR, '../setup.py'), 'r') as f:
+DIR = os.path.dirname("__file__")
+with open(os.path.join(DIR, "../setup.py"), "r") as f:
     for line in f:
-        if 'version=' in line:
-            setup_version = line.split('\'')[1]
+        if "version=" in line:
+            setup_version = line.split('"')[1]
             break
 
 # -- General configuration ------------------------------------------------
 
 # If your documentation needs a minimal Sphinx version, state it here.
-#needs_sphinx = '1.0'
+# needs_sphinx = '1.0'
 
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 extensions = [
-    'sphinx.ext.autodoc',
-    'sphinx.ext.doctest',
-    'sphinx.ext.intersphinx',
+    "sphinx.ext.autodoc",
+    "sphinx.ext.doctest",
+    "sphinx.ext.intersphinx",
 ]
 
 # Add any paths that contain templates here, relative to this directory.
-templates_path = ['_templates']
+templates_path = ["_templates"]
 
 # The suffix of source filenames.
-source_suffix = '.rst'
+source_suffix = ".rst"
 
 # The encoding of source files.
-#source_encoding = 'utf-8-sig'
+# source_encoding = 'utf-8-sig'
 
 # The master toctree document.
-master_doc = 'index'
+master_doc = "index"
 
 # General information about the project.
-project = 'eth-account'
-copyright = '2020, The Ethereum Foundation'
+project = "eth-account"
+copyright = "2020, The Ethereum Foundation"
 
 __version__ = setup_version
 # The version info for the project you're documenting, acts as replacement for
@@ -62,178 +62,181 @@
 # built documents.
 #
 # The short X.Y version.
-version = '.'.join(__version__.split('.')[:2])
+version = ".".join(__version__.split(".")[:2])
 # The full version, including alpha/beta/rc tags.
 release = __version__
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
-#language = None
+# language = None
 
 # There are two options for replacing |today|: either, you set today to some
 # non-false value, then it is used:
-#today = ''
+# today = ''
 # Else, today_fmt is used as the format for a strftime call.
-#today_fmt = '%B %d, %Y'
+# today_fmt = '%B %d, %Y'
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
 exclude_patterns = [
-    '_build',
-    'modules.rst',
-    'eth_account.internal.rst',
-    'eth_account.hdaccount.rst',
+    "_build",
+    "modules.rst",
+    "eth_account.internal.rst",
+    "eth_account.hdaccount.rst",
 ]
 
 # The reST default role (used for this markup: `text`) to use for all
 # documents.
-#default_role = None
+# default_role = None
 
 # If true, '()' will be appended to :func: etc. cross-reference text.
-#add_function_parentheses = True
+# add_function_parentheses = True
 
 # If true, the current module name will be prepended to all description
 # unit titles (such as .. function::).
-#add_module_names = True
+# add_module_names = True
 
 # If true, sectionauthor and moduleauthor directives will be shown in the
 # output. They are ignored by default.
-#show_authors = False
+# show_authors = False
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
+pygments_style = "sphinx"
 
 # A list of ignored prefixes for module index sorting.
-#modindex_common_prefix = []
+# modindex_common_prefix = []
 
 # If true, keep warnings as "system message" paragraphs in the built documents.
-#keep_warnings = False
+# keep_warnings = False
 
 
 # -- Options for HTML output ----------------------------------------------
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-html_theme = 'sphinx_rtd_theme'
+html_theme = "sphinx_rtd_theme"
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
 # documentation.
-#html_theme_options = {}
+# html_theme_options = {}
 
 # Add any paths that contain custom themes here, relative to this directory.
 
 # The name for this set of Sphinx documents.  If None, it defaults to
 # "<project> v<release> documentation".
-#html_title = None
+# html_title = None
 
 # A shorter title for the navigation bar.  Default is the same as html_title.
-#html_short_title = None
+# html_short_title = None
 
 # The name of an image file (relative to this directory) to place at the top
 # of the sidebar.
-#html_logo = None
+# html_logo = None
 
 # The name of an image file (within the static path) to use as favicon of the
 # docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32
 # pixels large.
-#html_favicon = None
+# html_favicon = None
 
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+html_static_path = ["_static"]
 
 # Add any extra paths that contain custom files (such as robots.txt or
 # .htaccess) here, relative to this directory. These files are copied
 # directly to the root of the documentation.
-#html_extra_path = []
+# html_extra_path = []
 
 # If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
 # using the given strftime format.
-#html_last_updated_fmt = '%b %d, %Y'
+# html_last_updated_fmt = '%b %d, %Y'
 
 # If true, SmartyPants will be used to convert quotes and dashes to
 # typographically correct entities.
-#html_use_smartypants = True
+# html_use_smartypants = True
 
 # Custom sidebar templates, maps document names to template names.
-#html_sidebars = {}
+# html_sidebars = {}
 
 # Additional templates that should be rendered to pages, maps page names to
 # template names.
-#html_additional_pages = {}
+# html_additional_pages = {}
 
 # If false, no module index is generated.
-#html_domain_indices = True
+# html_domain_indices = True
 
 # If false, no index is generated.
-#html_use_index = True
+# html_use_index = True
 
 # If true, the index is split into individual pages for each letter.
-#html_split_index = False
+# html_split_index = False
 
 # If true, links to the reST sources are added to the pages.
-#html_show_sourcelink = True
+# html_show_sourcelink = True
 
 # If true, "Created using Sphinx" is shown in the HTML footer. Default is True.
-#html_show_sphinx = True
+# html_show_sphinx = True
 
 # If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.
-#html_show_copyright = True
+# html_show_copyright = True
 
 # If true, an OpenSearch description file will be output, and all pages will
 # contain a <link> tag referring to it.  The value of this option must be the
 # base URL from which the finished HTML is served.
-#html_use_opensearch = ''
+# html_use_opensearch = ''
 
 # This is the file name suffix for HTML files (e.g. ".xhtml").
-#html_file_suffix = None
+# html_file_suffix = None
 
 # Output file base name for HTML help builder.
-htmlhelp_basename = 'eth_accountdoc'
+htmlhelp_basename = "eth_accountdoc"
 
 
 # -- Options for LaTeX output ---------------------------------------------
 
 latex_elements = {
-# The paper size ('letterpaper' or 'a4paper').
-#'papersize': 'letterpaper',
-
-# The font size ('10pt', '11pt' or '12pt').
-#'pointsize': '10pt',
-
-# Additional stuff for the LaTeX preamble.
-#'preamble': '',
+    # The paper size ('letterpaper' or 'a4paper').
+    #'papersize': 'letterpaper',
+    # The font size ('10pt', '11pt' or '12pt').
+    #'pointsize': '10pt',
+    # Additional stuff for the LaTeX preamble.
+    #'preamble': '',
 }
 
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title,
 #  author, documentclass [howto, manual, or own class]).
 latex_documents = [
-  ('index', 'eth_account.tex', 'eth-account Documentation',
-   'The Ethereum Foundation', 'manual'),
+    (
+        "index",
+        "eth_account.tex",
+        "eth-account Documentation",
+        "The Ethereum Foundation",
+        "manual",
+    ),
 ]
 
 # The name of an image file (relative to this directory) to place at the top of
 # the title page.
-#latex_logo = None
+# latex_logo = None
 
 # For "manual" documents, if this is true, then toplevel headings are parts,
 # not chapters.
-#latex_use_parts = False
+# latex_use_parts = False
 
 # If true, show page references after internal links.
-#latex_show_pagerefs = False
+# latex_show_pagerefs = False
 
 # If true, show URL addresses after external links.
-#latex_show_urls = False
+# latex_show_urls = False
 
 # Documents to append as an appendix to all manuals.
-#latex_appendices = []
+# latex_appendices = []
 
 # If false, no module index is generated.
-#latex_domain_indices = True
+# latex_domain_indices = True
 
 
 # -- Options for manual page output ---------------------------------------
@@ -241,12 +244,17 @@
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
 man_pages = [
-    ('index', 'eth_account', 'eth-account Documentation',
-     ['The Ethereum Foundation'], 1)
+    (
+        "index",
+        "eth_account",
+        "eth-account Documentation",
+        ["The Ethereum Foundation"],
+        1,
+    )
 ]
 
 # If true, show URL addresses after external links.
-#man_show_urls = False
+# man_show_urls = False
 
 
 # -- Options for Texinfo output -------------------------------------------
@@ -255,36 +263,43 @@
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-  ('index', 'eth-account', 'eth-account Documentation',
-   'The Ethereum Foundation', 'eth-account', 'Sign Ethereum transactions and messages with local private keys',
-   'Miscellaneous'),
+    (
+        "index",
+        "eth-account",
+        "eth-account Documentation",
+        "The Ethereum Foundation",
+        "eth-account",
+        "Sign Ethereum transactions and messages with local private keys",
+        "Miscellaneous",
+    ),
 ]
 
 # Documents to append as an appendix to all manuals.
-#texinfo_appendices = []
+# texinfo_appendices = []
 
 # If false, no module index is generated.
-#texinfo_domain_indices = True
+# texinfo_domain_indices = True
 
 # How to display URL addresses: 'footnote', 'no', or 'inline'.
-#texinfo_show_urls = 'footnote'
+# texinfo_show_urls = 'footnote'
 
 # If true, do not generate a @detailmenu in the "Top" node's menu.
-#texinfo_no_detailmenu = False
+# texinfo_no_detailmenu = False
 
 # -- Intersphinx configuration ------------------------------------------------
 
 intersphinx_mapping = {
-    'python': ('https://docs.python.org/3.6', None),
-    'web3': ('http://web3py.readthedocs.io/en/latest/', None),
-    'hexbytes': ('http://hexbytes.readthedocs.io/en/latest/', None),
+    "python": ("https://docs.python.org/3.6", None),
+    "web3": ("http://web3py.readthedocs.io/en/latest/", None),
+    "hexbytes": ("http://hexbytes.readthedocs.io/en/latest/", None),
 }
 
 # -- Doctest configuration ----------------------------------------
 
 import doctest
 
-doctest_default_flags = (0
+doctest_default_flags = (
+    0
     | doctest.DONT_ACCEPT_TRUE_FOR_1
     | doctest.ELLIPSIS
     | doctest.IGNORE_EXCEPTION_DETAIL
diff --git a/eth_account/hdaccount/deterministic.py b/eth_account/hdaccount/deterministic.py
index 56a3223e..a427d897 100644
--- a/eth_account/hdaccount/deterministic.py
+++ b/eth_account/hdaccount/deterministic.py
@@ -71,12 +71,9 @@ class Node(int):
 
     def __new__(cls, index):
         if 0 > index or index > 2**31:
-            raise ValidationError(
-                f"{cls} cannot be initialized with value {index}"
-            )
+            raise ValidationError(f"{cls} cannot be initialized with value {index}")
 
-        # mypy/typeshed bug requires type ignore: https://github.com/python/typeshed/issues/2686
-        obj = int.__new__(cls, index + cls.OFFSET)  # type: ignore
+        obj = int.__new__(cls, index + cls.OFFSET)
         obj.index = index
         return obj
 
@@ -117,6 +114,7 @@ class SoftNode(Node):
     """
     Soft node (unhardened), where value = index .
     """
+
     TAG = ""  # No tag
     OFFSET = 0x0  # No offset
 
@@ -125,6 +123,7 @@ class HardNode(Node):
     """
     Hard node, where value = index + BIP32_HARDENED_CONSTANT .
     """
+
     TAG = "H"  # "H" (or "'") means hard node (but use "H" for clarity)
     OFFSET = 0x80000000  # 2**31, BIP32 "Hardening constant"
 
@@ -206,7 +205,7 @@ def __init__(self, path: str):
         if len(path) < 1:
             raise ValidationError("Cannot parse path from empty string.")
 
-        nodes = path.split('/')  # Should at least make 1 entry in resulting list
+        nodes = path.split("/")  # Should at least make 1 entry in resulting list
         if nodes[0] not in BASE_NODE_IDENTIFIERS:
             raise ValidationError(f'Path is not valid: "{path}". Must start with "m"')
 
@@ -228,8 +227,8 @@ def encode(self) -> str:
         """
         Encodes this class to a string (reversing the decoding in the constructor).
         """
-        encoded_path = ('m',) + tuple(node.encode() for node in self._path)
-        return '/'.join(encoded_path)
+        encoded_path = ("m",) + tuple(node.encode() for node in self._path)
+        return "/".join(encoded_path)
 
     def derive(self, seed: bytes) -> bytes:
         """
diff --git a/newsfragments/183.misc.rst b/newsfragments/183.misc.rst
new file mode 100644
index 00000000..49729e75
--- /dev/null
+++ b/newsfragments/183.misc.rst
@@ -0,0 +1 @@
+Update mypy version, fix corresponding errors.
diff --git a/setup.py b/setup.py
index 266ba9f5..3415e3de 100644
--- a/setup.py
+++ b/setup.py
@@ -6,24 +6,24 @@
 )
 
 extras_require = {
-    'test': [
+    "test": [
         "hypothesis>=4.18.0,<5",
         "pytest>=6.2.5,<7",
         "pytest-xdist",
         "tox==3.14.6",
     ],
-    'lint': [
+    "lint": [
         "flake8==3.7.9",
         "isort>=4.2.15,<5",
-        "mypy==0.770",
+        "mypy==0.910",
         "pydocstyle>=5.0.0,<6",
     ],
-    'doc': [
+    "doc": [
         "Sphinx>=1.6.5,<2",
         "sphinx_rtd_theme>=0.1.9,<1",
         "towncrier>=21.9.0",
     ],
-    'dev': [
+    "dev": [
         "bumpversion>=0.5.3,<1",
         "pytest-watch>=4.1.0,<5",
         "wheel",
@@ -32,33 +32,35 @@
     ],
 }
 
-extras_require['dev'] = (
-    extras_require['dev'] +  # noqa: W504
-    extras_require['test'] +  # noqa: W504
-    extras_require['lint'] +  # noqa: W504
-    extras_require['doc']
+extras_require["dev"] = (
+    extras_require["dev"]
+    + extras_require["test"]  # noqa: W504
+    + extras_require["lint"]  # noqa: W504
+    + extras_require["doc"]  # noqa: W504
 )
 
 
-with open('./README.md') as readme:
+with open("./README.md") as readme:
     long_description = readme.read()
 
 
 setup(
-    name='eth-account',
+    name="eth-account",
     # *IMPORTANT*: Don't manually change the version here. Use `make bump`, as described in readme
-    version='0.5.8',
+    version="0.5.8",
     description="""eth-account: Sign Ethereum transactions and messages with local private keys""",
     long_description=long_description,
-    long_description_content_type='text/markdown',
-    author='The Ethereum Foundation',
-    author_email='snakecharmers@ethereum.org',
-    url='https://github.com/ethereum/eth-account',
+    long_description_content_type="text/markdown",
+    author="The Ethereum Foundation",
+    author_email="snakecharmers@ethereum.org",
+    url="https://github.com/ethereum/eth-account",
     include_package_data=True,
-    package_data={"eth_account": [
-        "py.typed",
-        "hdaccount/wordlist/*.txt",
-    ]},
+    package_data={
+        "eth_account": [
+            "py.typed",
+            "hdaccount/wordlist/*.txt",
+        ]
+    },
     install_requires=[
         "bitarray>=1.2.1,<3",
         "eth-abi>=2.0.0b7,<3",
@@ -67,27 +69,27 @@
         "eth-rlp>=0.1.2,<2",
         "eth-utils>=1.3.0,<2",
         "hexbytes>=0.1.0,<1",
-        "rlp>=1.0.0,<3"
+        "rlp>=1.0.0,<3",
     ],
-    python_requires='>=3.6, <4',
+    python_requires=">=3.6, <4",
     extras_require=extras_require,
-    py_modules=['eth_account'],
+    py_modules=["eth_account"],
     license="MIT",
     zip_safe=False,
-    keywords='ethereum',
+    keywords="ethereum",
     packages=find_packages(exclude=["tests", "tests.*"]),
     classifiers=[
-        'Development Status :: 3 - Alpha',
-        'Intended Audience :: Developers',
-        'License :: OSI Approved :: MIT License',
-        'Natural Language :: English',
-        'Operating System :: MacOS',
-        'Operating System :: POSIX',
-        'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.6',
-        'Programming Language :: Python :: 3.7',
-        'Programming Language :: Python :: 3.8',
-        'Programming Language :: Python :: 3.9',
-        'Programming Language :: Python :: 3.10',
+        "Development Status :: 3 - Alpha",
+        "Intended Audience :: Developers",
+        "License :: OSI Approved :: MIT License",
+        "Natural Language :: English",
+        "Operating System :: MacOS",
+        "Operating System :: POSIX",
+        "Programming Language :: Python :: 3",
+        "Programming Language :: Python :: 3.6",
+        "Programming Language :: Python :: 3.7",
+        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
+        "Programming Language :: Python :: 3.10",
     ],
 )