import base64
import pandas as pd
from IPython.display import HTML

def create_download_link( df, title = "Download CSV file", filename = "data.csv"):
    csv = df.to_csv()
    b64 = base64.b64encode(csv.encode())
    payload = b64.decode()
    html = '{title}'
    html = html.format(payload=payload,title=title,filename=filename)
    return HTML(html)

df = pd.DataFrame(data = [[1,2],[3,4]], columns=['Col 1', 'Col 2'])
create_download_link(df)