Can't update icon url

[washedgram]

I'm trying to set a custom webhook icon image but it looks like it's not updating past the default Slack app image. Here is my code:

import slackpy

webhook = 'hookgoeshere'
channel = '#channel'
username = 'Updates'
icon_emoji = 'https://emojipedia-us.s3.dualstack.us-west-1.amazonaws.com/thumbs/240/apple/237/goat_1f410.png'
as_user = 'false'

hook = slackpy.SlackLogger(webhook, channel, username, icon_emoji)
hook.info(message = title_message, title = title, fields = extra_fields) # initialized in a section i didn't add here

The webhooks post normally other than the icon not updating. I think that the app has all the necesssary permissions, just confused as to at which step the icon_emoji variable isn't getting updated.