Python - pandas read csv in loop

import pandas as pd

# --- functions ---

def read_part(start, size):
    try:
        df = pd.read_csv('data.csv', skiprows=start, nrows=size)
        return df
    except pd.io.common.EmptyDataError:
        return None

# --- main ---

start = 0
size = 8000
while True:
    print('start:', start)

    df = read_part(start, size)

    if df is None or len(df) < size:
        print('end of data')
        break

    start += size