Reversing a Sequence in Python

To reverse all elements of a sequence, specify a step with a negative value:

pythontxt = '123456789'
res = txt[::-1]

print(res) # '987654321'

Задание 1

Given a string:

pythontxt = '12345'

Turn it over:

python'54321'

Задание 2

Given a list:

pythonlst = ['c', 'b', 'a']

Turn it over:

python['a', 'b', 'c']

Задание 3

Given a string:

pythontxt = '123456789'

Get a slice of all its symbols at even positions in reverse order:

python'8642'