# import necessary libraries
import pandas as pd

# define your series and bins
bins = 10
series = pd.Series([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,\
                    12, 13, 14, 15, 16, 17, 18, 19, 20])

# use pd.qcut() method
result = pd.qcut(series, q = bins, labels = False)

# print the result
print(result)