# -*- coding: utf-8 -*-
import re
def name_of_email(addr):
    r=re.match(r'^\.?([a-zA-Z\s]+)\.?\s*\w*\@\w+?\.com$', addr)
    if(r):
        return r.group(1)
    else:
        return False

# 测试:
assert is_valid_email('someone@gmail.com')
assert is_valid_email('bill.gates@microsoft.com')
assert not is_valid_email('bob#example.com')
assert not is_valid_email('mr-bob@example.com')
print('ok')