[::-1] how it gives the reverse of list?

Answer 1

It is just agreed that negative steps would reverse the iterable.

Theoretical definition:

#(Does not handle arguments of nonsense.)
def slice(iterable, start=None, end=None, step=1):
#Handling None indices:
if start == None: start = 0
if end == None: end = len(iterable)

#Handling negative indices:
start = start % len(iterable)
end = (end - 1) % len(iterable) + 1

#If step is negative:
if step < 0:
start, end = end-1, start

#Filling new_list:
new_list = []
i = start

if step > 0:
while i < end:
new_list.append(iterable[i])
i += step

elif step < 0:
while i > end:
new_list.append(iterable[i])
i += step

#Returning new_list as type of the initial iterable:
return type(iterable)(new_list)

a = list(range(10))
b = slice(a, 10, 0, -2)
c = a[10:0:-2]

#b equals c

Answer 2

check out this code for more info on reversing lists in Python

https://code.sololearn.com/cWGyRXm9rC8i/?ref=app