Upgrade minimum python version

Author: wilbertliu

poetry.lock

@@ -15,7 +15,6 @@ classifiers = [
     "License :: OSI Approved :: MIT License",
     "Operating System :: OS Independent",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
@@ -24,7 +23,7 @@ classifiers = [
 ]
 
 [tool.poetry.dependencies]
-python = "^3.8.1"
+python = "^3.9"
 requests = "^2.31.0"
 
 [tool.poetry.group.dev.dependencies]
@@ -46,7 +45,7 @@ target-version = ['py38']
 include = '\.pyi?$'
 
 [tool.mypy]
-python_version = "3.8"
+python_version = "3.9"
 warn_return_any = true
 warn_unused_configs = true
 disallow_untyped_defs = true