Python Convert dataframe to numpy

import numpy as np
import pandas as pd

df = pd.DataFrame({'a': [1, 2, 3], 'b': [4, 5, 6]})

# convert to numpy array
np_array = df.values

# convert to numpy array with column names
np_array = df.values
np_array_with_col_names = np.insert(np_array, 0, df.columns, axis=0)

# convert to numpy array with row names
np_array = df.values
np_array_with_row_names = np.insert(np_array, 0, df.index, axis=1)