Update README.md

Author: naquiroz

README.md

@@ -1,2 +1,18 @@
 # python-sandbox
 A python sandbox for making testcases
+
+
+Requirements:
+- Python 3.6
+- Pipenv
+
+On command line:
+
+```bash
+python3 -m pip install pipenv
+```
+Then
+```bash
+pipenv install --dev
+```
+And you are ready for using it!