input: Write a function to filter out all negative numbers from the given matrix and return the modified matrix with all negative numbers replaced by 0. Use numpy for this operation.
  import numpy as np
  
  def filter_out_negative(matrix):
    matrix = np.array(matrix)
    matrix[matrix < 0] = 0
    return matrix
  
  assert np.array_equal(filter_out_negative([[-1, 2, -3], [-4, 5, 6], [-7, 8, 9]]), np.array([[0, 2, 0], [0, 5, 6], [0, 8, 9]]))
  assert np.array_equal(filter_out_negative([[3, 4, -5], [-6, 7, 8], [9, -10, 11]]), np.array([[3, 4, 0], [0, 7, 8], [9, 0, 11]]))
  assert np.array_equal(filter_out_negative([[-1, -2, -3], [-4, -5, -6], [-7, -8, -9]]), np.array([[0, 0, 0], [0, 0, 0], [0, 0, 0]]))
  assert np.array_equal(filter_out_negative([[1, 2, 3], [4, 5, 6], [7, 8, 9]]), np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]]))
  assert np.array_equal(filter_out_negative([]), np.array([]))
output: 
  def filter_out_negative(matrix):
    matrix = np.array(matrix)
    matrix[matrix < 0] = 0
    return matrix
  