input: Write a function to design a data structure in Python to store integer values with methods to add values and find the minimum value. The function should return an instance of the data structure.
  
  class IntList:
      def __init__(self):
          self.values = []
     
      def add_value(self, value):
          self.values.append(value)
      
      def find_min(self):
          return min(self.values)
  
  assert isinstance(IntList(), IntList)
  list_instance = IntList()
  list_instance.add_value(5)
  list_instance.add_value(3)
  list_instance.add_value(8)
  assert list_instance.find_min() == 3
  assert list_instance.find_min() != 5
output: class IntList:
      def __init__(self):
          self.values = []
     
      def add_value(self, value):
          self.values.append(value)
      
      def find_min(self):
          return min(self.values)