nix instead of pip

Pipfile

@@ -1,12 +0,0 @@
-[[source]]
-name = "pypi"
-url = "https://pypi.org/simple"
-verify_ssl = true
-
-[dev-packages]
-
-[packages]
-python-telegram-bot = "*"
-
-[requires]
-python_version = "3.8"

default.nix

@@ -0,0 +1,10 @@
+let
+  pkgs = import <nixpkgs> {};
+in pkgs.mkShell {
+  packages = [
+    (pkgs.python3.withPackages (python-pkgs: [
+      python-pkgs.python-telegram-bot
+    ]))
+  ];
+}
+

requirements.txt

@@ -1,16 +0,0 @@
-#
-# These requirements were autogenerated by pipenv
-# To regenerate from the project's Pipfile, run:
-#
-#    pipenv lock --requirements
-#
-
--i https://pypi.org/simple
-certifi==2020.6.20
-cffi==1.14.2
-cryptography==3.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'
-decorator==4.4.2
-pycparser==2.20; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
-python-telegram-bot==12.8
-six==1.15.0; python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'
-tornado==6.0.4; python_version >= '3.5'