input: from typing import List
  
  def match_numeric_strings(strings: List[str]) -> List[str]:
      """
      Match all numeric strings in the given list.
      >>> match_numeric_strings(['123', 'abc123', '456', '789xyz'])
      ['123', '456', '789']
      """
      pattern = '^[0-9]+$'
      return [s for s in strings if re.match(pattern, s)]
output:     import re