diff --git a/poetry.lock b/poetry.lock
index 058c1f5..bc82f2f 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -102,25 +102,20 @@ version = "0.6.2"
 
 [[package]]
 category = "dev"
-description = "Discover and load entry points from installed packages."
-name = "entrypoints"
-optional = false
-python-versions = ">=2.7"
-version = "0.3"
-
-[[package]]
-category = "dev"
-description = "the modular source code checker: pep8, pyflakes and co"
+description = "the modular source code checker: pep8 pyflakes and co"
 name = "flake8"
 optional = false
-python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "3.7.9"
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,>=2.7"
+version = "3.8.1"
 
 [package.dependencies]
-entrypoints = ">=0.3.0,<0.4.0"
 mccabe = ">=0.6.0,<0.7.0"
-pycodestyle = ">=2.5.0,<2.6.0"
-pyflakes = ">=2.1.0,<2.2.0"
+pycodestyle = ">=2.6.0a1,<2.7.0"
+pyflakes = ">=2.2.0,<2.3.0"
+
+[package.dependencies.importlib-metadata]
+python = "<3.8"
+version = "*"
 
 [package.dependencies.typing]
 python = "<3.5"
@@ -134,6 +129,22 @@ optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "2.8"
 
+[[package]]
+category = "dev"
+description = "Read metadata from Python packages"
+marker = "python_version < \"3.8\""
+name = "importlib-metadata"
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,>=2.7"
+version = "1.1.3"
+
+[package.dependencies]
+zipp = ">=0.5"
+
+[package.extras]
+docs = ["sphinx", "rst.linker"]
+testing = ["packaging", "importlib-resources"]
+
 [[package]]
 category = "dev"
 description = "A Python utility / library to sort Python imports."
@@ -171,7 +182,7 @@ description = "Python style guide checker"
 name = "pycodestyle"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "2.5.0"
+version = "2.6.0"
 
 [[package]]
 category = "dev"
@@ -179,7 +190,7 @@ description = "passive checker of Python programs"
 name = "pyflakes"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "2.1.1"
+version = "2.2.0"
 
 [[package]]
 category = "dev"
@@ -247,8 +258,21 @@ version = "1.24.3"
 secure = ["pyOpenSSL (>=0.14)", "cryptography (>=1.3.4)", "idna (>=2.0.0)", "certifi", "ipaddress"]
 socks = ["PySocks (>=1.5.6,<1.5.7 || >1.5.7,<2.0)"]
 
+[[package]]
+category = "dev"
+description = "Backport of pathlib-compatible object wrapper for zip files"
+marker = "python_version < \"3.8\""
+name = "zipp"
+optional = false
+python-versions = ">=2.7"
+version = "1.2.0"
+
+[package.extras]
+docs = ["sphinx", "jaraco.packaging (>=3.2)", "rst.linker (>=1.9)"]
+testing = ["pathlib2", "unittest2", "jaraco.itertools", "func-timeout"]
+
 [metadata]
-content-hash = "fdb39febdf20db3253e61d0b0a78e87b926a425a0c4efae2aafd89a8fd84e732"
+content-hash = "6e76ea620cd271ebad90764aab286adbfa0d70ac5d70c6701d7ca5b0badff63d"
 python-versions = "^3.4"
 
 [metadata.files]
@@ -317,18 +341,18 @@ coveralls = [
 docopt = [
     {file = "docopt-0.6.2.tar.gz", hash = "sha256:49b3a825280bd66b3aa83585ef59c4a8c82f2c8a522dbe754a8bc8d08c85c491"},
 ]
-entrypoints = [
-    {file = "entrypoints-0.3-py2.py3-none-any.whl", hash = "sha256:589f874b313739ad35be6e0cd7efde2a4e9b6fea91edcc34e58ecbb8dbe56d19"},
-    {file = "entrypoints-0.3.tar.gz", hash = "sha256:c70dd71abe5a8c85e55e12c19bd91ccfeec11a6e99044204511f9ed547d48451"},
-]
 flake8 = [
-    {file = "flake8-3.7.9-py2.py3-none-any.whl", hash = "sha256:49356e766643ad15072a789a20915d3c91dc89fd313ccd71802303fd67e4deca"},
-    {file = "flake8-3.7.9.tar.gz", hash = "sha256:45681a117ecc81e870cbf1262835ae4af5e7a8b08e40b944a8a6e6b895914cfb"},
+    {file = "flake8-3.8.1-py2.py3-none-any.whl", hash = "sha256:6c1193b0c3f853ef763969238f6c81e9e63ace9d024518edc020d5f1d6d93195"},
+    {file = "flake8-3.8.1.tar.gz", hash = "sha256:ea6623797bf9a52f4c9577d780da0bb17d65f870213f7b5bcc9fca82540c31d5"},
 ]
 idna = [
     {file = "idna-2.8-py2.py3-none-any.whl", hash = "sha256:ea8b7f6188e6fa117537c3df7da9fc686d485087abf6ac197f9c46432f7e4a3c"},
     {file = "idna-2.8.tar.gz", hash = "sha256:c357b3f628cf53ae2c4c05627ecc484553142ca23264e593d327bcde5e9c3407"},
 ]
+importlib-metadata = [
+    {file = "importlib_metadata-1.1.3-py2.py3-none-any.whl", hash = "sha256:7c7f8ac40673f507f349bef2eed21a0e5f01ddf5b2a7356a6c65eb2099b53764"},
+    {file = "importlib_metadata-1.1.3.tar.gz", hash = "sha256:7a99fb4084ffe6dae374961ba7a6521b79c1d07c658ab3a28aa264ee1d1b14e3"},
+]
 isort = [
     {file = "isort-4.3.21-py2.py3-none-any.whl", hash = "sha256:6e811fcb295968434526407adb8796944f1988c5b65e8139058f2014cbe100fd"},
     {file = "isort-4.3.21.tar.gz", hash = "sha256:54da7e92468955c4fceacd0c86bd0ec997b0e1ee80d97f67c35a78b719dccab1"},
@@ -342,12 +366,12 @@ pathspec = [
     {file = "pathspec-0.7.0.tar.gz", hash = "sha256:562aa70af2e0d434367d9790ad37aed893de47f1693e4201fd1d3dca15d19b96"},
 ]
 pycodestyle = [
-    {file = "pycodestyle-2.5.0-py2.py3-none-any.whl", hash = "sha256:95a2219d12372f05704562a14ec30bc76b05a5b297b21a5dfe3f6fac3491ae56"},
-    {file = "pycodestyle-2.5.0.tar.gz", hash = "sha256:e40a936c9a450ad81df37f549d676d127b1b66000a6c500caa2b085bc0ca976c"},
+    {file = "pycodestyle-2.6.0-py2.py3-none-any.whl", hash = "sha256:2295e7b2f6b5bd100585ebcb1f616591b652db8a741695b3d8f5d28bdc934367"},
+    {file = "pycodestyle-2.6.0.tar.gz", hash = "sha256:c58a7d2815e0e8d7972bf1803331fb0152f867bd89adf8a01dfd55085434192e"},
 ]
 pyflakes = [
-    {file = "pyflakes-2.1.1-py2.py3-none-any.whl", hash = "sha256:17dbeb2e3f4d772725c777fabc446d5634d1038f234e77343108ce445ea69ce0"},
-    {file = "pyflakes-2.1.1.tar.gz", hash = "sha256:d976835886f8c5b31d47970ed689944a0262b5f3afa00a5a7b4dc81e5449f8a2"},
+    {file = "pyflakes-2.2.0-py2.py3-none-any.whl", hash = "sha256:0d94e0e05a19e57a99444b6ddcf9a6eb2e5c68d3ca1e98e90707af8152c90a92"},
+    {file = "pyflakes-2.2.0.tar.gz", hash = "sha256:35b2d75ee967ea93b55750aa9edbbf72813e06a66ba54438df2cfac9e3c27fc8"},
 ]
 regex = [
     {file = "regex-2020.2.20-cp27-cp27m-win32.whl", hash = "sha256:99272d6b6a68c7ae4391908fc15f6b8c9a6c345a46b632d7fdb7ef6c883a2bbb"},
@@ -413,3 +437,7 @@ urllib3 = [
     {file = "urllib3-1.24.3-py2.py3-none-any.whl", hash = "sha256:a637e5fae88995b256e3409dc4d52c2e2e0ba32c42a6365fee8bbd2238de3cfb"},
     {file = "urllib3-1.24.3.tar.gz", hash = "sha256:2393a695cd12afedd0dcb26fe5d50d0cf248e5a66f75dbd89a3d4eb333a61af4"},
 ]
+zipp = [
+    {file = "zipp-1.2.0-py2.py3-none-any.whl", hash = "sha256:e0d9e63797e483a30d27e09fffd308c59a700d365ec34e93cc100844168bf921"},
+    {file = "zipp-1.2.0.tar.gz", hash = "sha256:c70410551488251b0fee67b460fb9a536af8d6f9f008ad10ac51f615b6a521b1"},
+]
diff --git a/pyproject.toml b/pyproject.toml
index 1760c1e..835c532 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -15,7 +15,7 @@ requests = "2.*"
 [tool.poetry.dev-dependencies]
 coveralls = "^1.11.1"
 isort = "^4.3"
-flake8 = "^3.7.8 "
+flake8 = "^3.8.1"
 black = { version = "==19.10b0", allow-prereleases = true, python = "^3.6" }
 
 [build-system]