How to encode url in drupal 8?

It's a easy way to encode url in drupal 8 twig template. We just have to follow the simple steps:
Step 1. First create a variable like given example.

Example:
{% set return_url = render_var(url('<front>')) ~ 'contact?msg=success&region=americas' %}

Description: here
   return_url is the variable name and
   url('<front>') is the front page url and
   contact?msg=success&region=americas this section we are concating with " ~ " Tilde sign and
   render_var is the render that full url.

Step 2. Now we have to pass the url in src like given example.

Example: https://www.google.com?Return_URL={{ return_url|url_encode}}

Description: So just call the "return_url" with "url_encode" function in url query string. That will return the encoded url.


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