      def collect_incoming_data(self, data):
          try:
              smtpd.SMTPChannel.collect_incoming_data(self, data)
  
      def smtp_AUTH(self, arg):
          if arg == 'CRAM-MD5':
              # This is only the first part of the login process. But it's enough
              # for our tests.
 
</s> remove         # Ignore decode error in SSL/TLS connection tests as the test only
        # cares whether the connection attempt was made.
        with suppress(UnicodeDecodeError):
 </s> add         try: </s> remove with suppress(ImportError):
 </s> add try: </s> remove     with suppress(KeyError):
 </s> add     try:
        except UnicodeDecodeError:
            # Ignore decode error in SSL/TLS connection tests as the test only
            # cares whether the connection attempt was made.
            pass
      def collect_incoming_data(self, data):
          try:
              smtpd.SMTPChannel.collect_incoming_data(self, data)
        except UnicodeDecodeError:
            # Ignore decode error in SSL/TLS connection tests as the test only
            # cares whether the connection attempt was made.
            pass
  
      def smtp_AUTH(self, arg):
          if arg == 'CRAM-MD5':
              # This is only the first part of the login process. But it's enough
              # for our tests.
keep keep add keep keep keep keep keep
 Reverted "Fixed #27818 -- Replaced try/except/pass with contextlib.suppress()."

This reverts commit 550cb3a365dee4edfdd1563224d5304de2a57fda
because try/except performs better. 
tests/mail/tests.py