Unsupported operation :not writeable python
Solution 1:
You open the variable "file" as a read only then attempt to write to it:
file = open('ValidEmails.txt','r')
Instead, use the 'w' flag.
file = open('ValidEmails.txt','w')
...
file.write(email)
Solution 2:
file = open('ValidEmails.txt','wb')
file.write(email.encode('utf-8', 'ignore'))
This is solve your encode error also.