Support python 3.7 (#1)

* add 3.7

* add python version to ci

* fix stuff

.github/workflows/pytest.yml

@@ -5,9 +5,9 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [ '3.8', '3.9', '3.10' ]
+        python-version: [ '3.7', '3.8', '3.9', '3.10' ]
 
-    name: ${{ matrix.os }}
+    name: ${{ matrix.python-version }}
     steps:
       - uses: actions/checkout@v2
       - name: Setup Python

README.md

@@ -1,6 +1,6 @@
 # sigparse
 
-Backports python3.10 typing features into python3.8 and 3.9.
+Backports python3.10 typing features into python 3.7, 3.8, and 3.9.
 
 ## Example
 
@@ -10,7 +10,7 @@ import sigparse
 def func(param_a: list[str], param_b: str | int, param_c: tuple[int | None]):
     ...
 
-# This returns the same result in python 3.8, 3.9, and 3.10!
+# This returns the same result in python 3.7, 3.8, 3.9, and 3.10!
 sigparse.sigparse(func)
 ```
 

pyproject.toml

@@ -1,7 +1,7 @@
 [tool.poetry]
 name = "sigparse"
 version = "1.0.0"
-description = "Backports python3.10 typing features into python3.8 and python3.9."
+description = "Backports python3.10 typing features into python 3.7 and newer."
 authors = ["Lunarmagpie <bambolambo0@gmail.com>"]
 license = "MIT"
 readme = "README.md"
@@ -11,7 +11,7 @@ homepage = "https://github.com/Lunarmagpie/sigparse"
 "Bug Tracker" = "https://github.com/python-poetry/poetry/issues"
 
 [tool.poetry.dependencies]
-python = ">=3.8"
+python = ">=3.7"
 forbiddenfruit = "^0.1.4"
 
 [tool.poetry.dev-dependencies]

sigparse/__init__.py

@@ -84,14 +84,14 @@ def has_default(self) -> bool:
         """
         Return `True` if this argument has a default value.
         """
-        return not self.default is inspect._empty
+        return self.default is not inspect._empty
 
     @property
     def has_annotation(self) -> bool:
         """
         Return `True` if this argument has an annotation.
         """
-        return not self.annotation is inspect._empty
+        return self.annotation is not inspect._empty
 
 
 def _convert_signiture(