How to add a new variable with a custom name to an object?

Question

Python

Not needed yet, but very interesting... Let's say I want to add to

class Test:
   def __init__(self):
      self.sma=None
t=Test()

new variables are allowed in an exaggeratedly similar way

for i in range(0,3):
    exec('t.sma_'+str(i)+'=None')

and in the end I want to get

print(t.sma_0) // None
print(t.sma_1) // None
print(t.sma_2) // None
print(t.sma_3) // None

How is this done correctly? And how often is this generally used?

Answer 1

What exactly bothers you?
New attributes can be added to the object in an obvious way: If the attribute name is non-constant - setattr() :
t.sma_1 = 17

setattr(t, "sma_" + str(2), 17)
# можно и так
t.__setattr__("sma_" + str(2), 17)