update CONTRIBUTING

CONTRIBUTING.md

@@ -1,36 +1,21 @@
 # How to contribute
+To contribute to this library, first checkout the code. Then create a new virtual environment:
 
-## Dependencies
+    cd pypums
+    python -m venv venv
+    source venv/bin/activate
 
-We use `poetry` to manage the [dependencies](https://github.com/python-poetry/poetry).
-If you dont have `poetry` installed, you should run the command below.
+Or if you are using `pipenv`:
 
-```bash
-make download-poetry
-```
+    pipenv shell
 
-To install dependencies and prepare [`pre-commit`](https://pre-commit.com/) hooks you would need to run `install` command:
+Now install the dependencies and test dependencies:
 
-```bash
-make install
-```
+    pip install -e '.[test]'
 
-To activate your `virtualenv` run `poetry shell`.
+To run the tests:
 
-## Codestyle
-
-After you run `make install` you can execute the automatic code formatting.
-
-```bash
-make codestyle
-```
-
-### Checks
-
-Many checks are configured for this project. Command `make check-style` will run black diffs, darglint docstring style and mypy.
-The `make check-safety` command will look at the security of your code.
-
-You can also use `STRICT=1` flag to make the check be strict.
+    pytest
 
 ### Before submitting
 
@@ -39,9 +24,6 @@ Before submitting your code please do the following steps:
 1. Add any changes you want
 1. Add tests for the new changes
 1. Edit documentation if you have changed something significant
-1. Run `make codestyle` to format your changes.
-1. Run `STRICT=1 make check-style` to ensure that types and docs are correct
-1. Run `STRICT=1 make check-safety` to ensure that security of your code is correct
 
 ## Other help