Remote Windows command execution over WinRM using python and Kerberos authentication

Hello experts
I am successful at running a command in a remote Windows server. I achieve this by installing WinRM in the remote Windows server, and also executing the following python script inside a Linux container which has Python installed:

from winrm.protocol import Protocol
winrm_url = 'http://xxxxxxxxx.xx.xxxxx.com:5985/wsman'
win_connect = Protocol(endpoint=winrm_url,transport='kerberos')
shell_id = win_connect.open_shell()
ps_script = """dir"""
command_id = win_connect.run_command(shell_id, ps_script)
output,error_value,exit_status = win_connect.get_command_output(shell_id, command_id)
output
error_value

By the way, and of course, I have already initiated a Kerberos ticket for the computer which is creating the remote session, otherwise this wouldn't work. The issue that I'm facing is: if I run my script the first time I get the following error:

kerberos.GSSError: (('Unspecified GSS failure.  Minor code may provide more information', 851968), ('Server not found in Kerberos database', -1765328377))

If I run it again it just works: it displays the contents of the remote directory.

Here are my results - captured in the second run attempt.

>>> output
' Volume in drive C is SYSTEM\r\n Volume Serial Number is XXXX-XXXX\r\n\r\n Directory of C:\\Users\\xxxx_xxxx\r\n\r\n06/1                                                                                0/2015  05:56 PM    <DIR>          .\r\n06/10/2015  05:56 PM    <DIR>          ..\r\n08/07/2014  11:28 AM    <DIR>                                                                                          Desktop\r\n06/10/2015  05:56 PM    <DIR>          Documents\r\n08/22/2013  09:39 AM    <DIR>          Downloads\r\n08/22                                                                                /2013  09:39 AM    <DIR>          Favorites\r\n08/22/2013  09:39 AM    <DIR>          Links\r\n08/22/2013  09:39 AM    <DI                                                                                R>          Music\r\n08/22/2013  09:39 AM    <DIR>          Pictures\r\n08/22/2013  09:39 AM    <DIR>          Saved Games                                                                                \r\n08/22/2013  09:39 AM    <DIR>          Videos\r\n               0 File(s)              0 bytes\r\n              11 Dir                                                                                (s)  562,262,183,936 bytes free\r\n'


If I went to run this again, this would again fail (third attempt) but if I do a fourth try, then it works again.

I'd like it to just work every single time I run it. (Best case scenario) Another option would be to understand where the problem is originating and if possible fix this root cause. I could go with a try/catch approach but only if there was no way to fix this error.