def test_check_input_with_numbers(): assert check_input(['1', '3', '2', '4']) == False
def test_check_input_with_zero_elements(): assert check_input([]) == True
def test_check_input_with_letters(): assert check_input(['fdsa', 'dfa', 'fdsafsd']) == True
def test_check_input_with_only_one_element(): assert check_input(['1']) == True
def test_check_input_with_numbers_and_letters(): assert check_input(['1', '3', '2', 'fdsafsd']) == True