input: Write a python function to create an instance of the Coach class and return its string representation.
  assert create_coach("John", "Warriors") == "The coach of Warriors is John."
  assert create_coach("Alex", "Tigers") == "The coach of Tigers is Alex."
  assert create_coach("Sam", "Lions") == "The coach of Lions is Sam."
output: class Coach:
      def __init__(self, name, team):
          self.name = name
          self.team = team
  
      def __str__(self):
          return f"The coach of {self.team} is {self.name}."
  
  def create_coach(name, team):
      coach = Coach(name, team)
      return str(coach)