import numpy as np

north = np.array([[10, 11, 12], [13, 14, 15]])
south = np.array([[20, 21, 22]])
east = np.array([[30], [31]])

by_row = np.concatenate((north, south), axis=0)
expected_by_row = np.array([[10, 11, 12], [13, 14, 15], [20, 21, 22]])
np.testing.assert_array_equal(by_row, expected_by_row)

by_column = np.concatenate((north, east), axis=1)
expected_by_column = np.array([[10, 11, 12, 30], [13, 14, 15, 31]])
np.testing.assert_array_equal(by_column, expected_by_column)

print("north shape:", north.shape)
print("south shape:", south.shape)
print("east shape:", east.shape)
print("by row:")
for row in by_row:
    print(" ", row.tolist())
print("by row shape:", by_row.shape)
print("by column:")
for row in by_column:
    print(" ", row.tolist())
print("by column shape:", by_column.shape)