input: Write a python function to create a 20x30 matrix with random float numbers between 0 and 1.
  assert len(matrix)==20
  assert len(matrix[0])==30
  assert all(0 <= num <= 1 for row in matrix for num in row)
output: import random
  
  def create_random_matrix():
      matrix = [[random.random() for _ in range(30)] for _ in range(20)]
      return matrix