square brackets after a function call

Question

I am a total novice at Python, and have come across a piece of code that confuses me.

ts, pkt2 = capPort2.wait(1, 45)[0]

The previous line

Answer 1

This means that return value of the wait function is either list or tuple and 0 it is an index of the element from this output. For example:

def func(numericValue):
    return list(str(numericValue))

res = func(1000)
res[0] - > 1

Or:

def convert(value, to_type):
    #do something
    return resuls, convertedValue

res = convert(1100, str)
res[0] - > True