writing a Series with a multindex header does not write the header

[sdementen]

Range("A1").value = df[column_name]
(with df having a multiindex) leaves empty the header while
Range("A1").value = df[[column_name]] writes the header properly

[ghost]

Can you attach a snippet we can run that will reproduce the bug?

[sdementen]

here you are

import pandas
import xlwings

df = pandas.DataFrame(data=1, index=[1, 2, 3, 4], columns=pandas.MultiIndex.from_tuples([("A", "foo"), ("B", "baz")]))
wb = xlwings.books.add()
wb.sheets[0].range("A1").value = df[("A", "foo")]   # bug, no header
wb.sheets[0].range("E1").value = df       # ok, header there