Filter out Strings from an Array

Create a function that takes a list of non-negative integers and strings and return a new list without the strings.

Examples

filter_list([1, 2, "a", "b"]) ➞ [1, 2]

filter_list([1, "a", "b", 0, 15]) ➞ [1, 0, 15]

filter_list([1, 2, "aasf", "1", "123", 123]) ➞ [1, 2, 123]

Notes

• Zero is a non-negative integer.
• The given list only has integers and strings.
• Numbers in the list should not repeat.
• The original order must be maintained.