NotImplementedError for (CORREL, MEDIAN, SLOPE, PRODUCT, PMT, PV, RATE, DATEDIF, WEEKDAY, WEEKNUM) functions

[frmZtH]

Describe the bug
It seems that the some functions do not seem to be supported.
Such as (CORREL, MEDIAN, SLOPE, PRODUCT, PMT, PV, RATE, DATEDIF, WEEKDAY, WEEKNUM).

To Reproduce
func = formulas.Parser().ast('=MEDIAN(A1,A2,A3,A4)')[1].compile()
func(1, 2, 3, 4)

Expected behavior
It should return value.

Screenshots
raise NotImplementedError
NotImplementedError
During handling of the above exception, another exception occurred:
raise DispatcherError( schedula.utils.exc.DispatcherError: ("Failed DISPATCHING '%s' due to:\n %r", 'MEDIAN', NotImplementedError())

Desktop (please complete the following information):

• OS: [Windows 10]
• Version [1.1.0]

[sada1993]

Also noticed this with the ADDRESS function in excel.

[vinci1it2000]

>>> import formulas 
>>> func = formulas.Parser().ast('=MEDIAN(A1,A2,A3,A4)')[1].compile()
>>> func(1, 2, 3, 4)
2.5