python-3.5, timestamp to YYYYmmDDHHMMSS
<p>Hello to every saturday workers!
I need to convert a timestamp to YYYYmmDDHHMMSS. The following works well</p>

<pre><code>    timestamp=now_var[27:38]                      # timestamp string 
dth_now=(                               # string date heure 
    datetime.datetime.fromtimestamp(
        int(timestamp)
     ).strftime('%Y%m%d_%H%M%S')
)                                       # a string
</code></pre>

<p>but gives an alert</p>

<pre><code>  File "C:\_Python\kWh_compare.py", line 35, in &lt;module&gt;
).strftime('%Y%m%d_%H%M%S')
ValueError: invalid literal for int() with base 10: ''
</code></pre>

<p>Where is the problem ?
thanks</p>