Use str.format
to insert the password into the string:
pw = getpass.getpass()
from subprocess import Popen, PIPE, STDOUT
ssh_conn = Popen(["ssh", "-t", server, "sudo -S cp /etc/"+map, "/etc/"+map + "." +fulltime], stdout=PIPE, stdin=PIPE, stderr=STDOUT)
ssh_conn.communicate(input='{0}\n'.format(pw))[0]