diff --git a/poetry.lock b/poetry.lock
index 1eda556..a1c9a8c 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -5,7 +5,6 @@ description = "Atomic file writes."
 category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-marker = "sys_platform == \"win32\""
 
 [[package]]
 name = "attrs"
@@ -16,9 +15,9 @@ optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [package.extras]
-dev = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface", "sphinx", "sphinx-rtd-theme", "pre-commit"]
+dev = ["coverage[toml] (>=5.0.2)", "hypothesis", "pre-commit", "pympler", "pytest (>=4.3.0)", "six", "sphinx", "sphinx-rtd-theme", "zope.interface"]
 docs = ["sphinx", "sphinx-rtd-theme", "zope.interface"]
-tests = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface"]
+tests = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface"]
 
 [[package]]
 name = "bump2version"
@@ -37,12 +36,15 @@ optional = false
 python-versions = "*"
 
 [[package]]
-name = "chardet"
-version = "3.0.4"
-description = "Universal encoding detector for Python 2 and 3"
+name = "charset-normalizer"
+version = "2.0.12"
+description = "The Real First Universal Charset Detector. Open, modern and actively maintained alternative to Chardet."
 category = "dev"
 optional = false
-python-versions = "*"
+python-versions = ">=3.5.0"
+
+[package.extras]
+unicode_backport = ["unicodedata2"]
 
 [[package]]
 name = "codecov"
@@ -63,7 +65,6 @@ description = "Cross-platform colored terminal text."
 category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
-marker = "sys_platform == \"win32\""
 
 [[package]]
 name = "coverage"
@@ -73,14 +74,12 @@ category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4"
 
+[package.dependencies]
+toml = {version = "*", optional = true, markers = "extra == \"toml\""}
+
 [package.extras]
 toml = ["toml"]
 
-[package.dependencies]
-[package.dependencies.toml]
-version = "*"
-optional = true
-
 [[package]]
 name = "filelock"
 version = "3.0.12"
@@ -98,14 +97,11 @@ optional = false
 python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,>=2.7"
 
 [package.dependencies]
+importlib-metadata = {version = "*", markers = "python_version < \"3.8\""}
 mccabe = ">=0.6.0,<0.7.0"
 pycodestyle = ">=2.6.0a1,<2.7.0"
 pyflakes = ">=2.2.0,<2.3.0"
 
-[package.dependencies.importlib-metadata]
-version = "*"
-python = "<3.8"
-
 [[package]]
 name = "idna"
 version = "2.10"
@@ -121,15 +117,14 @@ description = "Read metadata from Python packages"
 category = "dev"
 optional = false
 python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,>=2.7"
-marker = "python_version < \"3.8\""
-
-[package.extras]
-docs = ["sphinx", "rst.linker"]
-testing = ["packaging", "pep517", "importlib-resources (>=1.3)"]
 
 [package.dependencies]
 zipp = ">=0.5"
 
+[package.extras]
+docs = ["rst.linker", "sphinx"]
+testing = ["importlib-resources (>=1.3)", "packaging", "pep517"]
+
 [[package]]
 name = "iniconfig"
 version = "1.0.1"
@@ -161,16 +156,15 @@ description = "Optional static typing for Python"
 category = "dev"
 optional = false
 python-versions = ">=3.5"
-marker = "python_version < \"3.8\" or python_version >= \"3.8\""
-
-[package.extras]
-dmypy = ["psutil (>=4.0)"]
 
 [package.dependencies]
 mypy-extensions = ">=0.4.3,<0.5.0"
 typed-ast = ">=1.4.0,<1.5.0"
 typing-extensions = ">=3.7.4"
 
+[package.extras]
+dmypy = ["psutil (>=4.0)"]
+
 [[package]]
 name = "mypy-extensions"
 version = "0.4.3"
@@ -178,7 +172,6 @@ description = "Experimental type system extensions for programs checked with the
 category = "dev"
 optional = false
 python-versions = "*"
-marker = "python_version < \"3.8\" or python_version >= \"3.8\""
 
 [[package]]
 name = "packaging"
@@ -200,14 +193,12 @@ category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
+[package.dependencies]
+importlib-metadata = {version = ">=0.12", markers = "python_version < \"3.8\""}
+
 [package.extras]
 dev = ["pre-commit", "tox"]
 
-[package.dependencies]
-[package.dependencies.importlib-metadata]
-version = ">=0.12"
-python = "<3.8"
-
 [[package]]
 name = "py"
 version = "1.9.0"
@@ -248,14 +239,11 @@ category = "dev"
 optional = false
 python-versions = ">=3.5"
 
-[package.extras]
-checkqa_mypy = ["mypy (0.780)"]
-testing = ["argcomplete", "hypothesis (>=3.56)", "mock", "nose", "requests", "xmlschema"]
-
 [package.dependencies]
-atomicwrites = ">=1.0"
+atomicwrites = {version = ">=1.0", markers = "sys_platform == \"win32\""}
 attrs = ">=17.4.0"
-colorama = "*"
+colorama = {version = "*", markers = "sys_platform == \"win32\""}
+importlib-metadata = {version = ">=0.12", markers = "python_version < \"3.8\""}
 iniconfig = "*"
 more-itertools = ">=4.0.0"
 packaging = "*"
@@ -263,9 +251,9 @@ pluggy = ">=0.12,<1.0"
 py = ">=1.8.2"
 toml = "*"
 
-[package.dependencies.importlib-metadata]
-version = ">=0.12"
-python = "<3.8"
+[package.extras]
+checkqa_mypy = ["mypy (==0.780)"]
+testing = ["argcomplete", "hypothesis (>=3.56)", "mock", "nose", "requests", "xmlschema"]
 
 [[package]]
 name = "pytest-cov"
@@ -275,13 +263,13 @@ category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 
-[package.extras]
-testing = ["fields", "hunter", "process-tests (2.0.2)", "six", "pytest-xdist", "virtualenv"]
-
 [package.dependencies]
 coverage = ">=4.4"
 pytest = ">=4.6"
 
+[package.extras]
+testing = ["fields", "hunter", "process-tests (==2.0.2)", "pytest-xdist", "six", "virtualenv"]
+
 [[package]]
 name = "pytest-flake8"
 version = "1.0.6"
@@ -304,33 +292,29 @@ python-versions = ">=3.5"
 
 [package.dependencies]
 filelock = ">=3.0"
+mypy = [
+    {version = ">=0.700", markers = "python_version >= \"3.8\""},
+    {version = ">=0.500", markers = "python_version < \"3.8\""},
+]
 pytest = ">=3.5"
 
-[[package.dependencies.mypy]]
-version = ">=0.500"
-python = "<3.8"
-
-[[package.dependencies.mypy]]
-version = ">=0.700"
-python = ">=3.8"
-
 [[package]]
 name = "requests"
-version = "2.24.0"
+version = "2.27.1"
 description = "Python HTTP for Humans."
 category = "dev"
 optional = false
-python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
-
-[package.extras]
-security = ["pyOpenSSL (>=0.14)", "cryptography (>=1.3.4)"]
-socks = ["PySocks (>=1.5.6,<1.5.7 || >1.5.7)", "win-inet-pton"]
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*"
 
 [package.dependencies]
 certifi = ">=2017.4.17"
-chardet = ">=3.0.2,<4"
-idna = ">=2.5,<3"
-urllib3 = ">=1.21.1,<1.25.0 || >1.25.0,<1.25.1 || >1.25.1,<1.26"
+charset-normalizer = {version = ">=2.0.0,<2.1.0", markers = "python_version >= \"3\""}
+idna = {version = ">=2.5,<4", markers = "python_version >= \"3\""}
+urllib3 = ">=1.21.1,<1.27"
+
+[package.extras]
+socks = ["PySocks (>=1.5.6,!=1.5.7)", "win-inet-pton"]
+use_chardet_on_py3 = ["chardet (>=3.0.2,<5)"]
 
 [[package]]
 name = "six"
@@ -355,7 +339,6 @@ description = "a fork of Python 2 and 3 ast modules with type comment support"
 category = "dev"
 optional = false
 python-versions = "*"
-marker = "python_version < \"3.8\" or python_version >= \"3.8\""
 
 [[package]]
 name = "typing-extensions"
@@ -364,11 +347,10 @@ description = "Backported and Experimental Type Hints for Python 3.5+"
 category = "dev"
 optional = false
 python-versions = "*"
-marker = "python_version < \"3.8\" or python_version >= \"3.8\""
 
 [[package]]
 name = "urllib3"
-version = "1.25.10"
+version = "1.26.5"
 description = "HTTP library with thread-safe connection pooling, file post, and more."
 category = "dev"
 optional = false
@@ -376,8 +358,8 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4"
 
 [package.extras]
 brotli = ["brotlipy (>=0.6.0)"]
-secure = ["certifi", "cryptography (>=1.3.4)", "idna (>=2.0.0)", "pyOpenSSL (>=0.14)", "ipaddress"]
-socks = ["PySocks (>=1.5.6,<1.5.7 || >1.5.7,<2.0)"]
+secure = ["certifi", "cryptography (>=1.3.4)", "idna (>=2.0.0)", "ipaddress", "pyOpenSSL (>=0.14)"]
+socks = ["PySocks (>=1.5.6,!=1.5.7,<2.0)"]
 
 [[package]]
 name = "wrapt"
@@ -394,14 +376,13 @@ description = "Backport of pathlib-compatible object wrapper for zip files"
 category = "dev"
 optional = false
 python-versions = ">=3.6"
-marker = "python_version < \"3.8\""
 
 [package.extras]
-docs = ["sphinx", "jaraco.packaging (>=3.2)", "rst.linker (>=1.9)"]
-testing = ["jaraco.itertools", "func-timeout"]
+docs = ["jaraco.packaging (>=3.2)", "rst.linker (>=1.9)", "sphinx"]
+testing = ["func-timeout", "jaraco.itertools"]
 
 [metadata]
-lock-version = "1.0"
+lock-version = "1.1"
 python-versions = "^3.6"
 content-hash = "62e08f76a94c6fa77997bc50be72f8090f31063a7725002727b9522a49b68e64"
 
@@ -422,9 +403,9 @@ certifi = [
     {file = "certifi-2020.6.20-py2.py3-none-any.whl", hash = "sha256:8fc0819f1f30ba15bdb34cceffb9ef04d99f420f68eb75d901e9560b8749fc41"},
     {file = "certifi-2020.6.20.tar.gz", hash = "sha256:5930595817496dd21bb8dc35dad090f1c2cd0adfaf21204bf6732ca5d8ee34d3"},
 ]
-chardet = [
-    {file = "chardet-3.0.4-py2.py3-none-any.whl", hash = "sha256:fc323ffcaeaed0e0a02bf4d117757b98aed530d9ed4531e3e15460124c106691"},
-    {file = "chardet-3.0.4.tar.gz", hash = "sha256:84ab92ed1c4d4f16916e05906b6b75a6c0fb5db821cc65e70cbd64a3e2a5eaae"},
+charset-normalizer = [
+    {file = "charset-normalizer-2.0.12.tar.gz", hash = "sha256:2857e29ff0d34db842cd7ca3230549d1a697f96ee6d3fb071cfa6c7393832597"},
+    {file = "charset_normalizer-2.0.12-py3-none-any.whl", hash = "sha256:6881edbebdb17b39b4eaaa821b438bf6eddffb4468cf344f09f89def34a8b1df"},
 ]
 codecov = [
     {file = "codecov-2.1.9-py2.py3-none-any.whl", hash = "sha256:24545847177a893716b3455ac5bfbafe0465f38d4eb86ea922c09adc7f327e65"},
@@ -560,8 +541,8 @@ pytest-mypy = [
     {file = "pytest_mypy-0.7.0-py3-none-any.whl", hash = "sha256:e0505ace48d2b19fe686366fce6b4a2ac0d090423736bb6aa2e39554d18974b7"},
 ]
 requests = [
-    {file = "requests-2.24.0-py2.py3-none-any.whl", hash = "sha256:fe75cc94a9443b9246fc7049224f75604b113c36acb93f87b80ed42c44cbb898"},
-    {file = "requests-2.24.0.tar.gz", hash = "sha256:b3559a131db72c33ee969480840fff4bb6dd111de7dd27c8ee1f820f4f00231b"},
+    {file = "requests-2.27.1-py2.py3-none-any.whl", hash = "sha256:f22fa1e554c9ddfd16e6e41ac79759e17be9e492b3587efa038054674760e72d"},
+    {file = "requests-2.27.1.tar.gz", hash = "sha256:68d7c56fd5a8999887728ef304a6d12edc7be74f1cfa47714fc8b414525c9a61"},
 ]
 six = [
     {file = "six-1.15.0-py2.py3-none-any.whl", hash = "sha256:8b74bedcbbbaca38ff6d7491d76f2b06b3592611af620f8426e82dddb04a5ced"},
@@ -579,19 +560,28 @@ typed-ast = [
     {file = "typed_ast-1.4.1-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:269151951236b0f9a6f04015a9004084a5ab0d5f19b57de779f908621e7d8b75"},
     {file = "typed_ast-1.4.1-cp36-cp36m-manylinux1_i686.whl", hash = "sha256:24995c843eb0ad11a4527b026b4dde3da70e1f2d8806c99b7b4a7cf491612652"},
     {file = "typed_ast-1.4.1-cp36-cp36m-manylinux1_x86_64.whl", hash = "sha256:fe460b922ec15dd205595c9b5b99e2f056fd98ae8f9f56b888e7a17dc2b757e7"},
+    {file = "typed_ast-1.4.1-cp36-cp36m-manylinux2014_aarch64.whl", hash = "sha256:fcf135e17cc74dbfbc05894ebca928ffeb23d9790b3167a674921db19082401f"},
     {file = "typed_ast-1.4.1-cp36-cp36m-win32.whl", hash = "sha256:4e3e5da80ccbebfff202a67bf900d081906c358ccc3d5e3c8aea42fdfdfd51c1"},
     {file = "typed_ast-1.4.1-cp36-cp36m-win_amd64.whl", hash = "sha256:249862707802d40f7f29f6e1aad8d84b5aa9e44552d2cc17384b209f091276aa"},
     {file = "typed_ast-1.4.1-cp37-cp37m-macosx_10_9_x86_64.whl", hash = "sha256:8ce678dbaf790dbdb3eba24056d5364fb45944f33553dd5869b7580cdbb83614"},
     {file = "typed_ast-1.4.1-cp37-cp37m-manylinux1_i686.whl", hash = "sha256:c9e348e02e4d2b4a8b2eedb48210430658df6951fa484e59de33ff773fbd4b41"},
     {file = "typed_ast-1.4.1-cp37-cp37m-manylinux1_x86_64.whl", hash = "sha256:bcd3b13b56ea479b3650b82cabd6b5343a625b0ced5429e4ccad28a8973f301b"},
+    {file = "typed_ast-1.4.1-cp37-cp37m-manylinux2014_aarch64.whl", hash = "sha256:f208eb7aff048f6bea9586e61af041ddf7f9ade7caed625742af423f6bae3298"},
     {file = "typed_ast-1.4.1-cp37-cp37m-win32.whl", hash = "sha256:d5d33e9e7af3b34a40dc05f498939f0ebf187f07c385fd58d591c533ad8562fe"},
     {file = "typed_ast-1.4.1-cp37-cp37m-win_amd64.whl", hash = "sha256:0666aa36131496aed8f7be0410ff974562ab7eeac11ef351def9ea6fa28f6355"},
     {file = "typed_ast-1.4.1-cp38-cp38-macosx_10_15_x86_64.whl", hash = "sha256:d205b1b46085271b4e15f670058ce182bd1199e56b317bf2ec004b6a44f911f6"},
     {file = "typed_ast-1.4.1-cp38-cp38-manylinux1_i686.whl", hash = "sha256:6daac9731f172c2a22ade6ed0c00197ee7cc1221aa84cfdf9c31defeb059a907"},
     {file = "typed_ast-1.4.1-cp38-cp38-manylinux1_x86_64.whl", hash = "sha256:498b0f36cc7054c1fead3d7fc59d2150f4d5c6c56ba7fb150c013fbc683a8d2d"},
+    {file = "typed_ast-1.4.1-cp38-cp38-manylinux2014_aarch64.whl", hash = "sha256:7e4c9d7658aaa1fc80018593abdf8598bf91325af6af5cce4ce7c73bc45ea53d"},
     {file = "typed_ast-1.4.1-cp38-cp38-win32.whl", hash = "sha256:715ff2f2df46121071622063fc7543d9b1fd19ebfc4f5c8895af64a77a8c852c"},
     {file = "typed_ast-1.4.1-cp38-cp38-win_amd64.whl", hash = "sha256:fc0fea399acb12edbf8a628ba8d2312f583bdbdb3335635db062fa98cf71fca4"},
     {file = "typed_ast-1.4.1-cp39-cp39-macosx_10_15_x86_64.whl", hash = "sha256:d43943ef777f9a1c42bf4e552ba23ac77a6351de620aa9acf64ad54933ad4d34"},
+    {file = "typed_ast-1.4.1-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:92c325624e304ebf0e025d1224b77dd4e6393f18aab8d829b5b7e04afe9b7a2c"},
+    {file = "typed_ast-1.4.1-cp39-cp39-manylinux1_i686.whl", hash = "sha256:d648b8e3bf2fe648745c8ffcee3db3ff903d0817a01a12dd6a6ea7a8f4889072"},
+    {file = "typed_ast-1.4.1-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:fac11badff8313e23717f3dada86a15389d0708275bddf766cca67a84ead3e91"},
+    {file = "typed_ast-1.4.1-cp39-cp39-manylinux2014_aarch64.whl", hash = "sha256:0d8110d78a5736e16e26213114a38ca35cb15b6515d535413b090bd50951556d"},
+    {file = "typed_ast-1.4.1-cp39-cp39-win32.whl", hash = "sha256:b52ccf7cfe4ce2a1064b18594381bccf4179c2ecf7f513134ec2f993dd4ab395"},
+    {file = "typed_ast-1.4.1-cp39-cp39-win_amd64.whl", hash = "sha256:3742b32cf1c6ef124d57f95be609c473d7ec4c14d0090e5a5e05a15269fb4d0c"},
     {file = "typed_ast-1.4.1.tar.gz", hash = "sha256:8c8aaad94455178e3187ab22c8b01a3837f8ee50e09cf31f1ba129eb293ec30b"},
 ]
 typing-extensions = [
@@ -600,8 +590,8 @@ typing-extensions = [
     {file = "typing_extensions-3.7.4.3.tar.gz", hash = "sha256:99d4073b617d30288f569d3f13d2bd7548c3a7e4c8de87db09a9d29bb3a4a60c"},
 ]
 urllib3 = [
-    {file = "urllib3-1.25.10-py2.py3-none-any.whl", hash = "sha256:e7983572181f5e1522d9c98453462384ee92a0be7fac5f1413a1e35c56cc0461"},
-    {file = "urllib3-1.25.10.tar.gz", hash = "sha256:91056c15fa70756691db97756772bb1eb9678fa585d9184f24534b100dc60f4a"},
+    {file = "urllib3-1.26.5-py2.py3-none-any.whl", hash = "sha256:753a0374df26658f99d826cfe40394a686d05985786d946fbe4165b5148f5a7c"},
+    {file = "urllib3-1.26.5.tar.gz", hash = "sha256:a7acd0977125325f516bda9735fa7142b909a8d01e8b2e4c8108d0984e6e0098"},
 ]
 wrapt = [
     {file = "wrapt-1.12.1.tar.gz", hash = "sha256:b62ffa81fb85f4332a4f609cab4ac40709470da05643a082ec1eb88e6d9b97d7"},