Switch version dependencies to use >=

Author: meshy

CHANGELOG.md

@@ -7,6 +7,13 @@ Version numbers should follow https://semver.org/spec/v2.0.0.html
 
 ## [Unreleased]
 
+## Fixed
+
+- Use `>=` to define minimum version numbers, not `~X.Y.Z`.
+  This fixes an issue where installing alongside other versions of `attrs`
+  caused an error:
+  `django-schema-graph 2.2.0 depends on attrs<22.0.0 and >=21.4.0`
+
 
 ## [2.2.0] - 2022-10-26
 

pyproject.toml

@@ -40,8 +40,8 @@ classifiers = [
 
 
 [tool.poetry.dependencies]
-python = "^3.6"
-attrs = "^21.4.0"
+python = ">=3.6"
+attrs = ">=21.4.0"
 
 [tool.poetry.dev-dependencies]
 django-environ = "^0.4.5"