set up python provider

Author: jdhao

lua/globals.lua

@@ -1,5 +1,16 @@
 local utils = require("utils")
 
+local config_path = vim.fn.stdpath("config")
+local python3_path = vim.fs.joinpath(config_path, ".venv/bin/python3")
+if not vim.uv.fs_stat(python3_path) then
+  local msg = string.format(
+    "Python provider missing:\n  create a virtual env under nvim config and install pynvim!"
+  )
+  vim.api.nvim_echo({ { msg } }, true, { err = true })
+else
+  vim.g.python3_host_prog = python3_path
+end
+
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