diff --git a/poetry.lock b/poetry.lock
index 469d882..1afcf97 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -4,13 +4,13 @@ description = "Classes Without Boilerplate"
 name = "attrs"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "19.3.0"
+version = "20.2.0"
 
 [package.extras]
-azure-pipelines = ["coverage", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface", "pytest-azurepipelines"]
-dev = ["coverage", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface", "sphinx", "pre-commit"]
-docs = ["sphinx", "zope.interface"]
-tests = ["coverage", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface"]
+dev = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface", "sphinx", "sphinx-rtd-theme", "pre-commit"]
+docs = ["sphinx", "sphinx-rtd-theme", "zope.interface"]
+tests = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface"]
+tests_no_zope = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six"]
 
 [[package]]
 category = "dev"
@@ -18,7 +18,7 @@ description = "Code coverage measurement for Python"
 name = "coverage"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4"
-version = "5.2"
+version = "5.2.1"
 
 [package.extras]
 toml = ["toml"]
@@ -126,7 +126,7 @@ description = "Backported and Experimental Type Hints for Python 3.5+"
 name = "typing-extensions"
 optional = false
 python-versions = "*"
-version = "3.7.4.2"
+version = "3.7.4.3"
 
 [[package]]
 category = "main"
@@ -143,48 +143,49 @@ testing = ["jaraco.itertools", "func-timeout"]
 
 [metadata]
 content-hash = "b4d62848f08fa4f157e2ad425cd7f3fd91e301ef03e0097d52a6e324498ac5c5"
+lock-version = "1.0"
 python-versions = "^3.6"
 
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