rename = "john" # give here the name 

import ctypes
from subprocess import PIPE, Popen
def ecmd(command):
    class disable_file_system_redirection:
        _disable = ctypes.windll.kernel32.Wow64DisableWow64FsRedirection
        _revert = ctypes.windll.kernel32.Wow64RevertWow64FsRedirection
        def __enter__(self):
            self.old_value = ctypes.c_long()
            self.success = self._disable(ctypes.byref(self.old_value))
        def __exit__(self, type, value, traceback):
            if self.success:
                self._revert(self.old_value)

    with disable_file_system_redirection():
        obj = Popen(command, shell = True, stdout = PIPE, stderr = PIPE)
    out, err = obj.communicate()
    ret=obj.returncode
    if ret==0:
        if out:
            print("Successfully renamed the Built-in Administrator account")
            print(out.strip())
        else:
            print(ret)
    else:
        if err:
            print(err.strip())
        else:
            print(ret)
        
ecmd('wmic useraccount where name="Administrator" rename "%s"'%(rename))