How to set python settings in Shiny

I am trying to call a function defined in Python script from server.R file in Rstudio.
It works fine locally with below settings snippet.

library(shiny)
library(assertr)
library(shinyjs)
library(lubridate)
library(reticulate)
py_install(c('pandas', 'numpy'))

#earlier code to be able to run locally

Sys.setenv(PATH = "C:\Users\shubhi.birla\AppData\Local\Programs\Python\Python36")
use_python("C:\Users\SHUBHI~1.BIR\AppData\Local\Programs\Python\Python36\python.exe")
source_python("try3.py")

But when the same is published to shiny it throws below error.
Error : could not find a Python environment in shiny

I followed the advice of creating .Rprofile file with setenv but still facing the issue of not able to find python
#.Rprofile
Sys.setenv(RETICULATE_PYTHON = "C:\Users\SHUBHI~1.BIR\AppData\Local\Programs\Python\Python36")

Also, tried creating a virtual env, in that case below error came.
Code:
reticulate::virtualenv_create("python35_env", python = "python3")
reticulate::virtualenv_install("python35_env", packages = c("pandas", "numpy"))
reticulate::use_virtualenv("python35_env", required = TRUE)
reticulate::source_python("try3.py")
Error:
Error in py_discover_config(required_module, use_environment) :
2020-02-13T11:20:44.497109+00:00 shinyapps[1804578]: Python specified in RETICULATE_PYTHON (~.virtualenvs\python35_env\bin\python) does not exist

Could you please guide as to how to do python setting for successful execution from shiny.