UnicodeDecodeError: 'utf-8' codec can't decode byte 0xb6 in position 0: invalid start byte

[Νίκος]

I just started to have this error without changing nothing

in my index.html(template) and metrites.py(which ipen the template)

[Thu Jul 04 11:35:14 2013] [error] [client 108.162.229.97] Original 
exception was:
[Thu Jul 04 11:35:14 2013] [error] [client 108.162.229.97] Traceback 
(most recent call last):
[Thu Jul 04 11:35:14 2013] [error] [client 108.162.229.97]   File 
"/home/nikos/public_html/cgi-bin/metrites.py", line 19, in <module>
[Thu Jul 04 11:35:14 2013] [error] [client 108.162.229.97]     host = 
socket.gethostbyaddr( os.environ['REMOTE_ADDR'] )[0] or 'UnResolved'
[Thu Jul 04 11:35:14 2013] [error] [client 108.162.229.97] 
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xb6 in position 0: 
invalid start byte
[Thu Jul 04 11:35:14 2013] [error] [client 108.162.229.97] Premature end 
of script headers: metrites.py


Why cant it decode the starting byte? what starting byte is that?
-- 
What is now proved was at first only imagined!