Python ftp with timestamp

import os
import ftplib
import datetime
 
local = 'LOCATION/WHERE/YOU/WANT/TO/DOWNLOAD'
time_stamps = {}
 
with ftplib.FTP('ftp.your.host') as server:
    server.login(user='username', passwd='password')
    for name, params in server.mlsd():
        if name != '.' and name != '..':
            with open(os.path.join(local, name), 'w+b') as download:
                try:
                    server.retrbinary('RETR ' + name, download.write)
                    dt = params['modify']
                    time_stamps[name] = {
                        'modified': '{yy}-{mo}-{dd} {hh}:{mm}:{ss}.{ms}'.format(
                            yy = dt[:4],
                            mo = dt[4:6],
                            dd = dt[6:8],
                            hh = dt[8:10],
                            mm = dt[10:12],
                            ss = dt[12:14],
                            ms = dt[14:]
                        ),
                        'fetched': str(datetime.datetime.now())
                    }
                except ftplib.error_perm:
                    pass
 
print(time_stamps)