diff --git a/poetry.lock b/poetry.lock
index 3d8cc22..049750a 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1,22 +1,23 @@
 [[package]]
-category = "dev"
-description = "A small Python module for determining appropriate platform-specific dirs, e.g. a \"user data dir\"."
 name = "appdirs"
+version = "1.4.4"
+description = "A small Python module for determining appropriate platform-specific dirs, e.g. a \"user data dir\"."
+category = "dev"
 optional = false
 python-versions = "*"
-version = "1.4.4"
 
 [[package]]
-category = "dev"
-description = "The uncompromising code formatter."
 name = "black"
+version = "20.8b1"
+description = "The uncompromising code formatter."
+category = "dev"
 optional = false
 python-versions = ">=3.6"
-version = "20.8b1"
 
 [package.dependencies]
 appdirs = "*"
 click = ">=7.1.2"
+dataclasses = {version = ">=0.6", markers = "python_version < \"3.7\""}
 mypy-extensions = ">=0.4.3"
 pathspec = ">=0.6,<1"
 regex = ">=2020.1.8"
@@ -24,67 +25,63 @@ toml = ">=0.10.1"
 typed-ast = ">=1.4.0"
 typing-extensions = ">=3.7.4"
 
-[package.dependencies.dataclasses]
-python = "<3.7"
-version = ">=0.6"
-
 [package.extras]
 colorama = ["colorama (>=0.4.3)"]
 d = ["aiohttp (>=3.3.2)", "aiohttp-cors"]
 
 [[package]]
-category = "dev"
-description = "Python package for providing Mozilla's CA Bundle."
 name = "certifi"
+version = "2020.4.5.2"
+description = "Python package for providing Mozilla's CA Bundle."
+category = "dev"
 optional = false
 python-versions = "*"
-version = "2020.4.5.2"
 
 [[package]]
-category = "dev"
-description = "Universal encoding detector for Python 2 and 3"
 name = "chardet"
+version = "3.0.4"
+description = "Universal encoding detector for Python 2 and 3"
+category = "dev"
 optional = false
 python-versions = "*"
-version = "3.0.4"
 
 [[package]]
-category = "main"
-description = "Composable command line interface toolkit"
 name = "click"
+version = "7.1.2"
+description = "Composable command line interface toolkit"
+category = "main"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
-version = "7.1.2"
 
 [[package]]
-category = "main"
-description = "Extends click.Group to invoke a command without explicit subcommand name"
 name = "click-default-group"
+version = "1.2.2"
+description = "Extends click.Group to invoke a command without explicit subcommand name"
+category = "main"
 optional = false
 python-versions = "*"
-version = "1.2.2"
 
 [package.dependencies]
 click = "*"
 
 [[package]]
-category = "dev"
-description = "Code coverage measurement for Python"
 name = "coverage"
+version = "5.1"
+description = "Code coverage measurement for Python"
+category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4"
-version = "5.1"
 
 [package.extras]
 toml = ["toml"]
 
 [[package]]
-category = "dev"
-description = "Show coverage stats online via coveralls.io"
 name = "coveralls"
+version = "2.1.2"
+description = "Show coverage stats online via coveralls.io"
+category = "dev"
 optional = false
 python-versions = ">= 3.5"
-version = "2.1.2"
 
 [package.dependencies]
 coverage = ">=4.1,<6.0"
@@ -95,55 +92,50 @@ requests = ">=1.0.0"
 yaml = ["PyYAML (>=3.10)"]
 
 [[package]]
-category = "dev"
-description = "A backport of the dataclasses module for Python 3.6"
-marker = "python_version < \"3.7\""
 name = "dataclasses"
+version = "0.6"
+description = "A backport of the dataclasses module for Python 3.6"
+category = "dev"
 optional = false
 python-versions = "*"
-version = "0.6"
 
 [[package]]
-category = "dev"
-description = "Pythonic argument parser, that will make you smile"
 name = "docopt"
+version = "0.6.2"
+description = "Pythonic argument parser, that will make you smile"
+category = "dev"
 optional = false
 python-versions = "*"
-version = "0.6.2"
 
 [[package]]
-category = "dev"
-description = "the modular source code checker: pep8 pyflakes and co"
 name = "flake8"
+version = "3.8.4"
+description = "the modular source code checker: pep8 pyflakes and co"
+category = "dev"
 optional = false
 python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,>=2.7"
-version = "3.8.4"
 
 [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]
-python = "<3.8"
-version = "*"
-
 [[package]]
-category = "dev"
-description = "Internationalized Domain Names in Applications (IDNA)"
 name = "idna"
+version = "2.9"
+description = "Internationalized Domain Names in Applications (IDNA)"
+category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "2.9"
 
 [[package]]
-category = "dev"
-description = "Read metadata from Python packages"
-marker = "python_version < \"3.8\""
 name = "importlib-metadata"
+version = "1.6.1"
+description = "Read metadata from Python packages"
+category = "dev"
 optional = false
 python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,>=2.7"
-version = "1.6.1"
 
 [package.dependencies]
 zipp = ">=0.5"
@@ -153,81 +145,81 @@ docs = ["sphinx", "rst.linker"]
 testing = ["packaging", "pep517", "importlib-resources (>=1.3)"]
 
 [[package]]
-category = "dev"
-description = "A Python utility / library to sort Python imports."
 name = "isort"
+version = "5.6.2"
+description = "A Python utility / library to sort Python imports."
+category = "dev"
 optional = false
 python-versions = ">=3.6,<4.0"
-version = "5.5.4"
 
 [package.extras]
-colors = ["colorama (>=0.4.3,<0.5.0)"]
 pipfile_deprecated_finder = ["pipreqs", "requirementslib"]
 requirements_deprecated_finder = ["pipreqs", "pip-api"]
+colors = ["colorama (>=0.4.3,<0.5.0)"]
 
 [[package]]
-category = "dev"
-description = "McCabe checker, plugin for flake8"
 name = "mccabe"
+version = "0.6.1"
+description = "McCabe checker, plugin for flake8"
+category = "dev"
 optional = false
 python-versions = "*"
-version = "0.6.1"
 
 [[package]]
-category = "dev"
-description = "Experimental type system extensions for programs checked with the mypy typechecker."
 name = "mypy-extensions"
+version = "0.4.3"
+description = "Experimental type system extensions for programs checked with the mypy typechecker."
+category = "dev"
 optional = false
 python-versions = "*"
-version = "0.4.3"
 
 [[package]]
-category = "dev"
-description = "Utility library for gitignore style pattern matching of file paths."
 name = "pathspec"
+version = "0.8.0"
+description = "Utility library for gitignore style pattern matching of file paths."
+category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
-version = "0.8.0"
 
 [[package]]
-category = "dev"
-description = "Python style guide checker"
 name = "pycodestyle"
+version = "2.6.0"
+description = "Python style guide checker"
+category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "2.6.0"
 
 [[package]]
-category = "dev"
-description = "passive checker of Python programs"
 name = "pyflakes"
+version = "2.2.0"
+description = "passive checker of Python programs"
+category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "2.2.0"
 
 [[package]]
-category = "main"
-description = "Pure Python read/write support for ESRI Shapefile format"
 name = "pyshp"
+version = "2.1.2"
+description = "Pure Python read/write support for ESRI Shapefile format"
+category = "main"
 optional = false
 python-versions = ">= 2.7"
-version = "2.1.2"
 
 [[package]]
-category = "dev"
-description = "Alternative regular expression module, to replace re."
 name = "regex"
+version = "2020.6.7"
+description = "Alternative regular expression module, to replace re."
+category = "dev"
 optional = false
 python-versions = "*"
-version = "2020.6.7"
 
 [[package]]
-category = "dev"
-description = "Python HTTP for Humans."
 name = "requests"
+version = "2.23.0"
+description = "Python HTTP for Humans."
+category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
-version = "2.23.0"
 
 [package.dependencies]
 certifi = ">=2017.4.17"
@@ -240,12 +232,12 @@ security = ["pyOpenSSL (>=0.14)", "cryptography (>=1.3.4)"]
 socks = ["PySocks (>=1.5.6,<1.5.7 || >1.5.7)", "win-inet-pton"]
 
 [[package]]
-category = "main"
-description = "Geometric objects, predicates, and operations"
 name = "shapely"
+version = "1.7.1"
+description = "Geometric objects, predicates, and operations"
+category = "main"
 optional = false
 python-versions = "*"
-version = "1.7.1"
 
 [package.extras]
 all = ["numpy", "pytest", "pytest-cov"]
@@ -253,12 +245,12 @@ test = ["pytest", "pytest-cov"]
 vectorized = ["numpy"]
 
 [[package]]
-category = "main"
-description = "CLI tool and Python utility functions for manipulating SQLite databases"
 name = "sqlite-utils"
+version = "2.21"
+description = "CLI tool and Python utility functions for manipulating SQLite databases"
+category = "main"
 optional = false
 python-versions = "*"
-version = "2.21"
 
 [package.dependencies]
 click = "*"
@@ -270,47 +262,47 @@ docs = ["sphinx-rtd-theme", "sphinx-autobuild"]
 test = ["pytest", "black"]
 
 [[package]]
-category = "main"
-description = "Pretty-print tabular data"
 name = "tabulate"
+version = "0.8.7"
+description = "Pretty-print tabular data"
+category = "main"
 optional = false
 python-versions = "*"
-version = "0.8.7"
 
 [package.extras]
 widechars = ["wcwidth"]
 
 [[package]]
-category = "dev"
-description = "Python Library for Tom's Obvious, Minimal Language"
 name = "toml"
+version = "0.10.1"
+description = "Python Library for Tom's Obvious, Minimal Language"
+category = "dev"
 optional = false
 python-versions = "*"
-version = "0.10.1"
 
 [[package]]
-category = "dev"
-description = "a fork of Python 2 and 3 ast modules with type comment support"
 name = "typed-ast"
+version = "1.4.1"
+description = "a fork of Python 2 and 3 ast modules with type comment support"
+category = "dev"
 optional = false
 python-versions = "*"
-version = "1.4.1"
 
 [[package]]
-category = "dev"
-description = "Backported and Experimental Type Hints for Python 3.5+"
 name = "typing-extensions"
+version = "3.7.4.3"
+description = "Backported and Experimental Type Hints for Python 3.5+"
+category = "dev"
 optional = false
 python-versions = "*"
-version = "3.7.4.3"
 
 [[package]]
-category = "dev"
-description = "HTTP library with thread-safe connection pooling, file post, and more."
 name = "urllib3"
+version = "1.25.9"
+description = "HTTP library with thread-safe connection pooling, file post, and more."
+category = "dev"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4"
-version = "1.25.9"
 
 [package.extras]
 brotli = ["brotlipy (>=0.6.0)"]
@@ -318,22 +310,21 @@ secure = ["certifi", "cryptography (>=1.3.4)", "idna (>=2.0.0)", "pyOpenSSL (>=0
 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"
+version = "3.1.0"
+description = "Backport of pathlib-compatible object wrapper for zip files"
+category = "dev"
 optional = false
 python-versions = ">=3.6"
-version = "3.1.0"
 
 [package.extras]
 docs = ["sphinx", "jaraco.packaging (>=3.2)", "rst.linker (>=1.9)"]
 testing = ["jaraco.itertools", "func-timeout"]
 
 [metadata]
-content-hash = "3283de36d7f86a1c8efd177ac73601e6afa5f6c9f304362acddef9656d1f367e"
-lock-version = "1.0"
+lock-version = "1.1"
 python-versions = "^3.6"
+content-hash = "fbfc9e4b94454718272732c5274c483a6bf3ab21b828c4c338c9883c4d5db459"
 
 [metadata.files]
 appdirs = [
@@ -415,8 +406,8 @@ importlib-metadata = [
     {file = "importlib_metadata-1.6.1.tar.gz", hash = "sha256:0505dd08068cfec00f53a74a0ad927676d7757da81b7436a6eefe4c7cf75c545"},
 ]
 isort = [
-    {file = "isort-5.5.4-py3-none-any.whl", hash = "sha256:36f0c6659b9000597e92618d05b72d4181104cf59472b1c6a039e3783f930c95"},
-    {file = "isort-5.5.4.tar.gz", hash = "sha256:ba040c24d20aa302f78f4747df549573ae1eaf8e1084269199154da9c483f07f"},
+    {file = "isort-5.6.2-py3-none-any.whl", hash = "sha256:a30c567b88d7b73e448b0f30526eaf2f943f0627809e4f34b9c3271918d96c3e"},
+    {file = "isort-5.6.2.tar.gz", hash = "sha256:c2cfe5b621f62932677004f96f93c4b128dc457d957b0531f204641fe8adc8a6"},
 ]
 mccabe = [
     {file = "mccabe-0.6.1-py2.py3-none-any.whl", hash = "sha256:ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42"},
diff --git a/pyproject.toml b/pyproject.toml
index ef4ef9a..229d607 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -15,7 +15,7 @@ Shapely = "^1.6.4"
 pyshp = "^2.1.0"
 
 [tool.poetry.dev-dependencies]
-isort = "^5.5"
+isort = "^5.6"
 flake8 = "^3.8.4"
 black = { version = "==20.8b1", allow-prereleases = true }
 coveralls = "^2.1.2"