input: Write a function in Python to calculate the number of vowels present in a given string.  
  assert Check_Vow('corner','AaEeIiOoUu') == 2  
  assert Check_Vow('valid','AaEeIiOoUu') == 2  
  assert Check_Vow('true','AaEeIiOoUu') == 2
output: def Check_Vow(string, vowels):
      count = 0
      for char in string:
          if char in vowels:
              count += 1
      return count