diff --git a/poetry.lock b/poetry.lock
index 2718c32..be53fe5 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -173,7 +173,7 @@ flake8 = ">=3.5,<5"
 
 [[package]]
 name = "flake8-isort"
-version = "4.1.1"
+version = "4.1.2.post0"
 description = "flake8 plugin that integrates isort ."
 category = "dev"
 optional = false
@@ -182,7 +182,6 @@ python-versions = "*"
 [package.dependencies]
 flake8 = ">=3.2.1,<5"
 isort = ">=4.3.5,<6"
-testfixtures = ">=6.8.0,<7"
 
 [package.extras]
 test = ["pytest-cov"]
@@ -631,19 +630,6 @@ python-versions = ">=3.6"
 importlib-metadata = {version = ">=1.7.0", markers = "python_version < \"3.8\""}
 pbr = ">=2.0.0,<2.1.0 || >2.1.0"
 
-[[package]]
-name = "testfixtures"
-version = "6.18.5"
-description = "A collection of helpers and mock objects for unit tests and doc tests."
-category = "dev"
-optional = false
-python-versions = "*"
-
-[package.extras]
-build = ["setuptools-git", "wheel", "twine"]
-docs = ["sphinx", "zope.component", "sybil", "twisted", "mock", "django (<2)", "django"]
-test = ["pytest (>=3.6)", "pytest-cov", "pytest-django", "zope.component", "sybil", "twisted", "mock", "django (<2)", "django"]
-
 [[package]]
 name = "toml"
 version = "0.10.2"
@@ -691,7 +677,7 @@ testing = ["pytest (>=6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7.0"
-content-hash = "a53f23112d2909fe55a9a46ee713ae2652272b3b71e330a85f56ec5edcd456f8"
+content-hash = "ecb947e82e5ac5bb79d477e9007116471ef981b34d3b578401af6be0dbd0d4be"
 
 [metadata.files]
 anyconfig = [
@@ -789,8 +775,8 @@ flake8-eradicate = [
     {file = "flake8_eradicate-1.2.1-py3-none-any.whl", hash = "sha256:00d77faefb64cef18b3c1b48a004c3a2ad663aa3cf85650f422437d25ece6441"},
 ]
 flake8-isort = [
-    {file = "flake8-isort-4.1.1.tar.gz", hash = "sha256:d814304ab70e6e58859bc5c3e221e2e6e71c958e7005239202fee19c24f82717"},
-    {file = "flake8_isort-4.1.1-py3-none-any.whl", hash = "sha256:c4e8b6dcb7be9b71a02e6e5d4196cefcef0f3447be51e82730fb336fff164949"},
+    {file = "flake8-isort-4.1.2.post0.tar.gz", hash = "sha256:dee69bc3c09f0832df88acf795845db8a6673b79237371a05fa927ce095248e5"},
+    {file = "flake8_isort-4.1.2.post0-py3-none-any.whl", hash = "sha256:4f95b40706dbb507cff872b34683283662e945d6028d3c8257e69de5fc6b7446"},
 ]
 flake8-logging-format = [
     {file = "flake8-logging-format-0.6.0.tar.gz", hash = "sha256:ca5f2b7fc31c3474a0aa77d227e022890f641a025f0ba664418797d979a779f8"},
@@ -1056,10 +1042,6 @@ stevedore = [
     {file = "stevedore-3.5.0-py3-none-any.whl", hash = "sha256:a547de73308fd7e90075bb4d301405bebf705292fa90a90fc3bcf9133f58616c"},
     {file = "stevedore-3.5.0.tar.gz", hash = "sha256:f40253887d8712eaa2bb0ea3830374416736dc8ec0e22f5a65092c1174c44335"},
 ]
-testfixtures = [
-    {file = "testfixtures-6.18.5-py2.py3-none-any.whl", hash = "sha256:7de200e24f50a4a5d6da7019fb1197aaf5abd475efb2ec2422fdcf2f2eb98c1d"},
-    {file = "testfixtures-6.18.5.tar.gz", hash = "sha256:02dae883f567f5b70fd3ad3c9eefb95912e78ac90be6c7444b5e2f46bf572c84"},
-]
 toml = [
     {file = "toml-0.10.2-py2.py3-none-any.whl", hash = "sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b"},
     {file = "toml-0.10.2.tar.gz", hash = "sha256:b3bda1d108d5dd99f4a20d24d9c348e91c4db7ab1b749200bded2f839ccbe68f"},
diff --git a/pyproject.toml b/pyproject.toml
index dc55f08..87ef605 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -54,7 +54,7 @@ flake8-blind-except = "0.2.1"
 flake8-builtins = "1.5.3"
 flake8-docstrings = "1.6.0"
 flake8-eradicate = "1.2.1"
-flake8-isort = "4.1.1"
+flake8-isort = "4.1.2.post0"
 flake8-logging-format = "0.6.0"
 flake8-pep3101 = "1.3.0"
 flake8-polyfill = "1.0.2"