gh-35070: Document sage installation method with pip
    
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URL: #35070
Reported by: Sanjay Rijal
Reviewer(s): Alex J Best, Matthias Köppe, Sanjay Rijal

Author: Release Manager

README.md

@@ -394,6 +394,20 @@ in the Installation Guide.
     or JupyterLab installation, as described in [section
     "Launching SageMath"](https://doc.sagemath.org/html/en/installation/launching.html)
     in the installation manual.
+    
+Alternative Installation using PyPI
+---------------
+
+For installation of `sage` in python using `pip` you need to install `sagemath-standard`. First, activate your python virtual environment and follow these steps:
+
+            $ python3 -m pip install sage_conf
+            $ ls $(sage-config SAGE_SPKG_WHEELS)
+            $ python3 -m pip install $(sage-config SAGE_SPKG_WHEELS)/*.whl 
+            $ python3 -m pip install sagemath-standard
+
+You need to install `sage_conf`, a wheelhouse of various python packages. You can list the wheels using `ls $(sage-config SAGE_SPKG_WHEELS)`. After manual installation of these wheels, you can install the sage library, `sagemath-standard`. 
+
+**NOTE:** You can find `sage` and `sagemath` pip packages but with these packages, you will encounter `ModuleNotFoundError`.
 
 Troubleshooting
 ---------------