input: def check_validity_of_word(word: str) -> bool:
      """
      A word is deemed valid if:
  
      It contains at least 3 characters.
      It is comprised solely of digits (0-9), and English letters (both uppercase and lowercase).
      It has a minimum of one vowel.
      It has a minimum of one consonant.
      You are provided with a string word.
  
      Return true if the word meets the criteria, otherwise, return false.
  
      Notes:
  
      'a', 'e', 'i', 'o', 'u', and their uppercase equivalents are vowels.
      A consonant is defined as an English letter that is not a vowel.
  
      Examples:
      >>> word = "234Adas"
      true
      >>> word = "b3"
      false
      >>> word = "a3$e"
      false
  
      Constraints:
      1 <= word.length <= 20
      word consists of English uppercase and lowercase letters, digits, '@', '#', and '$'.
      """
output:     if len(word) < 3:
          return False
  
      vowels = set('aeiouAEIOU')
      has_vowel = has_consonant = False
      
      for char in word:
          if not char.isalnum():
              return False
          if char in vowels:
              has_vowel = True
          elif char.isalpha():
              has_consonant = True
  
      return has_vowel and has_consonant