I didn't use emails.utils for my solution. Find my code below.

Just to precise, I started by splitting username / domain and extension into differents variables, then, I have created 3 differents regex pattern, to check if each one works.

When it was done, I've removed the split for username / domain and extension, then merge the 3 differents regex pattern into a big one.

And finally, it pass all the tests :

# Enter your code here. Read input from STDIN. Print output to STDOUT
import re
import email.utils


n = int(input())
output = list()
for _ in range(n):
    current_line = input().split()
    if "@" in current_line[1]:
        current_name = current_line[0]
    
        current_mail = current_line[1]
        current_mail = current_mail[1:-1]
    
        pattern = r"^([A-Za-z][A-Za-z0-9\_\-\.]+)@([A-Za-z]+)([.])([A-Za-z]{1,3})$"
        
        # Debug check
        #print(bool(re.match(pattern, current_mail)))
    
        if bool(re.match(pattern, current_mail)):
            output.append(current_line)
        else:
            continue
    else:
        continue

for element in output:
    print(f"{element[0]} {element[1]}")

from email.utils import parseaddr import re

pattern = r'^[A-Za-z][a-zA-Z0-9.,-_]*@[a-zA-Z]+.[a-zA-Z]{1,3}$' input_no = input() address = [] for i in range(int(input_no)): e_input = input() address.append(e_input)

for i in range(int(input_no)): name,addr = parseaddr(address[i]) match = re.match(pattern,addr) if match: print(name + "<" + addr + ">") print('Valid email')

This was a very simple challenge. ~~Even without using email.utils, it would've been simple.~~

Update: I changed my submission to not use email.utils, just to be shorter and to depend on fewer modules. Basically, it's the simplest possible program to read all input lines and output only those that match a regex.

import re, sys

# I included support for "+" in the address.
# I hate when email address validators don't allow it.
# Note that this is only a regex exercise, not a real email
# address validation.  The ONLY TRUE way to validate an
# email address is to send a message to it and instruct the
# recipient to respond.  When their response is received, ONLY
# THEN can the email address be considered valid.

print(''.join(l for l in sys.stdin.readlines()[1:]
  if re.search(r'<[a-z][\w.+-]*@[a-z]+\.[a-z]{1,3}>', l, re.I)))

how to solve this code