'Returns the value specified with an ``index`` from ``list``.
The given list is never altered by this keyword.
Index ``0`` means the first position, ``1`` the second, and so on.
Similarly, ``-1`` is the last position, ``-2`` the second last, and so on.
Using an index that does not exist on the list causes an error.
The index can be either an integer or a string that can be converted
to an integer.
Examples (including Python equivalents in comments):
| ${x} = | Get From List | ${L5} | 0  | # L5[0]  |
| ${y} = | Get From List | ${L5} | -2 | # L5[-2] |
| ${x} = \'a\'
| ${y} = \'d\'
| ${L5} is not changed'

def get_from_list(self, list_, index):

    try:
        return list_[self._index_to_int(index)]
    except IndexError:
        self._index_error(list_, index)
