Human: Give me a Python code to 90 degree rotation of an array in 2d. Assistant: 
Here is a Python code to 90 degree rotation of an array in 2d

import numpy as np

def rotate_90(array):
    """
    Rotate the array by 90 degrees.
    """
    return np.rot90(array, 1)

# Enter the array
array = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])

# Calling the function
print((rotate_90(array)))

#Example Output
# [[3 6 9]
#  [2 5 8]
#  [1 4 7]]

#Remember to inspect code for bugs.