Fix for

ERROR 2019-01-17 16:16:12,854 send_tips_for_bounty_fulfiller 31563 140151191623424 unhashable type: 'list'
Traceback (most recent call last):
  File "/home/ubuntu/gitcoin/coin/app/dashboard/management/commands/send_tips_for_bounty_fulfiller.py", line 68, in handle
    tip = assign_tip_to(tip, fulfillment.fulfiller_github_username)
  File "/home/ubuntu/gitcoin/coin/app/dashboard/management/commands/send_tips_for_bounty_fulfiller.py", line 39, in assign_tip_to
    tip.emails = get_emails_master(handle)
  File "/home/ubuntu/gitcoin/coin/app/git/utils.py", line 378, in get_emails_master
    return list(set([to_email for category, to_email in emails_by_category.items()]))
TypeError: unhashable type: 'list'

app/git/utils.py

@@ -375,7 +375,14 @@ def get_emails_by_category(username):
 
 def get_emails_master(username):
     emails_by_category = get_emails_by_category(username)
-    return list(set([to_email for category, to_email in emails_by_category.items()]))
+    emails = []
+    for category, to_email in emails_by_category.items():
+        if type(to_email) is str:
+            emails.append(to_email)
+        if type(to_email) is list:
+            for email in to_email:
+                emails.append(email)
+    return list(set(emails))
 
 
 def search(query):