1. Write a function called chop that takes a list, modifies it by removing the first and last elements,
and returns None. For example:
>>> t = [1, 2, 3, 4, 5, 6]
>>> chop(t)
>>> t
[2, 3, 4, 5]
2. Write a function called list_median that takes a list and returns a new list. If the list has even
numbers of elements, the new list will have two elements. If the list has odd numbers of elements,
the new list will include only one element. For example:
>>> t1 = [5, 1, 2, 3, 4]
>>> list_median(t1)
[3]
>>> t2 = [8, 3, 10, 6]
>>> list_median(t2)
[6, 8]
3. Write a function called has_duplicates that takes a list and returns True if there is any element that
appears more than once. It should not modify the original list. For example:
>>> t1 = [5, 1, 2, 3, 4]
>>> has_duplicates(t1)
False
>>> t2 = [5, 1, 2, 3, 2, 8, 10]
>>> has_duplicates(t2)
True