Here, angle MBC = angle MCB, because MBC is an isosceles triangle,

So, tan MCB = AB / BC

MCB = tan inverse MCB

MBC = MCB (isosceles triangle)

import math

AB, BC = int(input()), int(input())

tan_MCB = AB / BC

MCB = math.degrees(math.atan(tan_MCB))

MBC = MCB # because MBC == MCB (isosceles triangles)

print(f"{round(MBC)}\u00B0")

what is chr(176)

Guys in a copy pen solve the Question using simple geometry then you will find the angle to be arctan of height and base then just apply it:

import math a=int(input()) b=int(input()) rad=math.atan(a/b) print(round(math.degrees(rad)),chr(176),sep="")

Using complex numbers:

from cmath import phase
from math import degrees
if __name__ == "__main__":
    degree_sign = u'\N{DEGREE SIGN}'
    
    AB, BC = float(input().strip()), float(input().strip())
    AC = pow(AB*AB + BC*BC,.5)
    A = complex(0,AB)
    C = complex(BC,0)
    K = A+C
    M = K/2
    radian = phase(M)
    degree = round(degrees(radian))
    print(f"{degree}{degree_sign}")