input: Write a function to create a Student object in Python with attributes name, age, and gender. The function should return the created Student object. If the required attributes are not provided, the function should return None.
  assert create_student("Alice", 20, "Female") == Student(name="Alice", age=20, gender="Female")
  assert create_student("Bob", 22, "Male") == Student(name="Bob", age=22, gender="Male")
  assert create_student("Charlie", 21) == None
  assert create_student("David") == None
  assert create_student() == None
output: def create_student(name=None, age=None, gender=None):
      if name is not None and age is not None and gender is not None:
          return Student(name=name, age=age, gender=gender)
      else:
          return None