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Adapted and simplified from Franck Albinet's exercises available here. Also presented by NSRC at APRICOT 2018.

...

import time 

year, month, day, hour, minute, second, ms, dayinyear = time.localtime()

nameCsv = '/flash/log/acq'
nameCsv = nameCsv + '{:04d}'.format(year)
nameCsv = nameCsv + '{:02d}'.format(month)
nameCsv = nameCsv + '{:02d}'.format(day)
nameCsv = nameCsv + '{:02d}'.format(hour)
nameCsv = nameCsv + '{:02d}'.format(minute)
nameCsv = nameCsv + '{:02d}'.format(second)
nameCsv = nameCsv + 'list.csv'

A second approach more succinct would be to take advantage of Python list comprehensions:

base = '/flash/log/acq/'
time_stamp = ''.join(['{:02d}'.format(i) for i in time.localtime()][:6])
name = base + time_stamp + 'list.csv'

Let's unpack this second

...

implementation:

time.localtime()

outputs a tuple (1970, 1, 1, 0, 21, 40, 3, 1) representing year, month, ...

• formatting integer to string with list comprehension

['{:02d}'.format(i) for i in time.localtime()

outputs ['1970', '01', '01', '00', '24', '05', '03', '01']

We keep only year, month, day, hour, min., sec. by slicing the list:

['{:02d}'.format(i) for i in time.localtime()][:6]

• last we join the list to a single string

''.join(['{:02d}'.format(i) for i in time.localtime()][:6])

outputs: '19700101002920'

We can now simply concatenate this substring with a prefix and suffix and that's done.

As it is a quite frequent operation, we could even encapsulate it in an helper function as below:

def get_log_filename(prefix, suffix):
    time_stamp = ''.join(['{:02d}'.format(i) for i in time.localtime()][:6])
    return prefix + time_stamp + suffix

and use it when required: get_log_filename('/flash/log/acq', 'list.csv')

Exercise

Write a script writing a file named "log.csv" in /flash/log/ folder so that:

• if the user pushes the button the pressing time and an incremented counter is saved;
• it the counter reaches 10, LED is switched on.