pandas.Timestamp.isoweekday
- 
Timestamp.isoweekday() - 
Return the day of the week represented by the date. Monday == 1 … Sunday == 7
 
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Licensed under the 3-clause BSD License.
    https://pandas.pydata.org/pandas-docs/version/0.24.2/reference/api/pandas.Timestamp.isoweekday.html