cannot run tha last code of< example tracking top traded products>

[sanguovbobo]

when i run the file < example tracking top traded products> last code, it shows: name "date" 'timedelta' is not defined

[sanguovbobo]

the code is as following:yesterday = date.today() - timedelta(days=1)
comtradeapicall.bulkDownloadTarifflineFile(subscription_key, directory, typeCode='C', freqCode='A', clCode='HS',
period=None, reporterCode=None, decompress=True,
publishedDateFrom=yesterday, publishedDateTo=None)

---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
Cell In[14], line 1
----> 1 yesterday = date.today() - timedelta(days=1)
      2 comtradeapicall.bulkDownloadTarifflineFile(subscription_key, directory, typeCode='C', freqCode='A', clCode='HS',
      3                                               period=None, reporterCode=None, decompress=True,
      4                                               publishedDateFrom=yesterday, publishedDateTo=None)

NameError: name 'date' is not defined