How to get the square root of a number to 100 decimal places without using any libraries or modules

Question

For a college assignment, I've been tasked to get the square root of a number to 100 decimal places I've found an easy way of getting the square root, but the output only goes as far as 52 decimal places before defaulting to outputting zeroes i.ie

def sqrt2():
    #if x**y == x to the power of y (or y times multiplication of x e.g. 2**3 == 2*2*2) then to calculate the square root change y to 1/2
    #e.g if 4 to the power of 2 == 16 then 16 to the power of 1/2 = 4 
    result = 2**(0.5)
    printResult = format(result, ',.100f')
    
    print(printResult)

sqrt2()

The output of this is 1.4142135623730951454746218587388284504413604736328125000000000000000000000000000000000000000000000000 so as you can see it defaults to zeroes around half way through the number. I understand why Python won't do more decimal places as its just an approximation https://docs.python.org/3.4/tutorial/floatingpoint.html Any way of making the result more accurate without using any imports/libraries etc.?