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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def insert_at(df, sample_date, values):
 """ Insert some values into a bi-temporal dataframe. This is like what would happen when we get a price correction. """

    observed_dt = dt(datetime.now())
    return multi_index_insert_row(df, [sample_date, observed_dt], values)