input: Write a function to sort a list of file paths based on the month and year parsed from the filename.
  assert sort_files(['prefix_01_2021.tif', 'prefix_12_2020.tif', 'prefix_03_2021.tif']) == ['prefix_12_2020.tif', 'prefix_01_2021.tif', 'prefix_03_2021.tif']
  assert sort_files(['data_02_2019.tif', 'data_11_2018.tif', 'data_05_2020.tif']) == ['data_11_2018.tif', 'data_02_2019.tif', 'data_05_2020.tif']
  assert sort_files(['file_10_2021.tif', 'file_01_2021.tif', 'file_05_2021.tif']) == ['file_01_2021.tif', 'file_05_2021.tif', 'file_10_2021.tif']
output: def sort_files(file_list):
      def extract_date(file_name):
          parts = file_name.split('_')
          month = int(parts[-2])
          year = int(parts[-1].split('.')[0])
          return (year, month)
      
      return sorted(file_list, key=extract_date)