python - DateOffset from Year to Month and Week -

i pulling chunk of data within range of time. pulling date , times column recvd_dttm. takes data starting year ago. want modify can pull month or day, pd.dateoffset(months=1) giving keyerror:1 error. same error if change days=7. works fine years=1. going on here?

df = pd.read_csv('mydata.csv')  # filter countries @ least 1 medal , sort df['recvd_dttm'] = pd.to_datetime(df['recvd_dttm'])  #only retrieve data before (ignore typos future dates) mask = df['recvd_dttm'] <= datetime.datetime.now() df = df.loc[mask] # first , last datetime final week of data  range_max = df['recvd_dttm'].max() range_min = range_max - pd.dateoffset(years=1)  # take slice final week of data df = df[(df['recvd_dttm'] >= range_min) &                 (df['recvd_dttm'] <= range_max)] 

edit: problem coming elsewhere in code!

have tried being more explicit pd.dateoffset acting on?

for example:

range_max = df['recvd_dttm'].max() range_min = range_max - (df['recvd_dttm']+pd.dateoffset(years=1)) 

then substitute month , days values.