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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 is_bday(date, bday=None):
 """ Return true iff the given date is a business day. Parameters date : :class:`pandas.Timestamp` Any value that can be converted to a pandas Timestamp--e.g., '2012-05-01', dt.datetime(2012, 5, 1, 3) bday : :class:`pandas.tseries.offsets.CustomBusinessDay` Defaults to `CustomBusinessDay(calendar=USFederalHolidayCalendar())`. Pass this parameter in performance-sensitive contexts, such as when calling this function in a loop. The creation of the `CustomBusinessDay` object is the performance bottleneck of this function. Cf. `pandas.tseries.offsets.CustomBusinessDay <http://pandas.pydata.org/pandas-docs/stable/timeseries.html#custom-business-days-experimental>`_. Returns ------- val : bool True iff `date` is a business day """

    _date = Timestamp(date)
    if bday is None:
        bday = CustomBusinessDay(calendar=USFederalHolidayCalendar())
    return _date == (_date + bday) - bday