imap send email by python

import imaplib
import email

def extract_body(payload):
    if isinstance(payload,str):
        return payload
    else:
        return '\n'.join([extract_body(part.get_payload()) for part in payload])

conn = imaplib.IMAP4_SSL("pop.gmail.com", 993)
conn.login("[e-mail]", "password")
#print "logined"
conn.select()
#typ, data = conn.search(None, 'UNSEEN')
typ, data = conn.search(None, '(SINCE "3-Aug-2011")')
#typ, data = conn.search(None, 'OR')
#typ, data = conn.search(None, '')
try:
    for num in data[0].split():
        typ, msg_data = conn.fetch(num, '(RFC822)')
        for response_part in msg_data:
            if isinstance(response_part, tuple):
                msg = email.message_from_string(response_part[1])
                subject=msg['subject']                   
                print(subject)
                #payload=msg.get_payload()
                #body=extract_body(payload)
                #print(body)
                #if 
                #conn.store(num, '+FLAGS', '\\Deleted')
        #conn.store(num, '+FLAGS', '\\Deleted')
        #conn.expunge()
        #typ, response = conn.store(num, '+FLAGS', r'(\Seen)')


#typ, data = M.search(None, 'ALL')
#for num in data[0].split():
   #M.store(num, '+FLAGS', '\\Deleted')
#M.expunge()

finally:
    try:
        conn.close()
    except:
        pass
    conn.logout()

imap protocol is here:

http://tools.ietf.org/html/rfc3501.html#page-35

IMAP search critera strings is here:

http://www.example-code.com/csharp/imap-search-critera.asp

IMAP Search Keys are as follows:

      ALL
         All messages in the mailbox; the default initial key for
         ANDing.

      ANSWERED
         Messages with the \Answered flag set.

      BCC 
         Messages that contain the specified string in the envelope
         structure's BCC field.

      BEFORE 
         Messages whose internal date (disregarding time and timezone)
         is earlier than the specified date.

      BODY 
         Messages that contain the specified string in the body of the
         message.

      CC 
         Messages that contain the specified string in the envelope
         structure's CC field.

      DELETED
         Messages with the \Deleted flag set.

      DRAFT
         Messages with the \Draft flag set.

      FLAGGED
         Messages with the \Flagged flag set.

      FROM 
         Messages that contain the specified string in the envelope
         structure's FROM field.

      HEADER  
         Messages that have a header with the specified field-name (as
         defined in [RFC-2822]) and that contains the specified string
         in the text of the header (what comes after the colon).  If the
         string to search is zero-length, this matches all messages that
         have a header line with the specified field-name regardless of
         the contents.

      KEYWORD 
         Messages with the specified keyword flag set.

      LARGER 
         Messages with an [RFC-2822] size larger than the specified
         number of octets.

      NEW
         Messages that have the \Recent flag set but not the \Seen flag.
         This is functionally equivalent to "(RECENT UNSEEN)".

      NOT 
         Messages that do not match the specified search key.

      OLD
         Messages that do not have the \Recent flag set.  This is
         functionally equivalent to "NOT RECENT" (as opposed to "NOT
         NEW").

      ON 
         Messages whose internal date (disregarding time and timezone)
         is within the specified date.

      OR  
         Messages that match either search key.

      RECENT
         Messages that have the \Recent flag set.

      SEEN
         Messages that have the \Seen flag set.

      SENTBEFORE 
         Messages whose [RFC-2822] Date: header (disregarding time and
         timezone) is earlier than the specified date.

      SENTON 
         Messages whose [RFC-2822] Date: header (disregarding time and
         timezone) is within the specified date.

      SENTSINCE 
         Messages whose [RFC-2822] Date: header (disregarding time and
         timezone) is within or later than the specified date.

      SINCE 
         Messages whose internal date (disregarding time and timezone)
         is within or later than the specified date.

      SMALLER 
         Messages with an [RFC-2822] size smaller than the specified
         number of octets.

      SUBJECT 
         Messages that contain the specified string in the envelope
         structure's SUBJECT field.

      TEXT 
         Messages that contain the specified string in the header or
         body of the message.

      TO 
         Messages that contain the specified string in the envelope
         structure's TO field.

      UID 
         Messages with unique identifiers corresponding to the specified
         unique identifier set.  Sequence set ranges are permitted.

      UNANSWERED
         Messages that do not have the \Answered flag set.

      UNDELETED
         Messages that do not have the \Deleted flag set.

      UNDRAFT
         Messages that do not have the \Draft flag set.

      UNFLAGGED
         Messages that do not have the \Flagged flag set.

      UNKEYWORD 
         Messages that do not have the specified keyword flag set.

      UNSEEN
         Messages that do not have the \Seen flag set.