Function eval(s As String) As Variant
eval = Evaluate(s)
End Function

Sub ReadFromCom()
    mymodule = Left(ThisWorkbook.name, (InStrRev(ThisWorkbook.name, ".", -1, vbTextCompare) - 1))
    RunPython "import " & mymodule & ";" & mymodule & ".ReadFromCom()"
End Sub

import xlwings as xw
import serial
import time
import pythoncom


def ReadFromCom():
    wb = xw.Book.caller()
    sh = wb.sheets[0]
    ser = serial.Serial(port='COM4', baudrate=9600)
    n=10
    while (n>0):
    # Check if incoming bytes are waiting to be read from the serial input 
    # buffer.
    # NB: for PySerial v3.0 or later, use property `in_waiting` instead of
    # function `inWaiting()` below!
      if (ser.inWaiting() > 0):
        # read the bytes and convert from binary array to ASCII
        data_str = ser.read(ser.inWaiting()).decode('ascii') 
        # print the incoming string without putting a new-line
        # ('\n') automatically after every print()
        #print(data_str, end='') 
        #return data_str
        sh["A1"].value = data_str
        n=n-1
    # Put the rest of your code you want here
    
    # Optional, but recommended: sleep 10 ms (0.01 sec) once per loop to let 
    # other threads on your PC run during this time. 
    time.sleep(0.01)

let
    Источник = Web.Page(Web.Contents("https://ru.investing.com/indices/rtsi-historical-data")),
    Data0 = Источник{0}[Data],
    #"Измененный тип" = Table.TransformColumnTypes(Data0,{{"Дата", type date}, {"Цена", type text}, {"Откр.", type text}, {"Макс.", type text}, {"Мин.", type text}, {"Объём", type text}, {"Изм. %", type text}}),
    #"Удаленные столбцы" = Table.RemoveColumns(#"Измененный тип",{"Откр.", "Макс.", "Мин.", "Объём", "Изм. %"})
in
    #"Удаленные столбцы"

Function F(x As Double) As Double

If x < 0 Then F = Sqr(1 + x ^ 2)
If x >= 0 And x <= 3 Then
    F = 2 * x ^ 2 * Cos(2 * x)
Else
    F = (1 + Abs(x)) / ((x ^ 2 + x + 1) ^ (1 / 3))
End If
End Function