Sum of distributions

Questions
#1

Hello,
give the following PyMC3 code:

import pymc3 as pm

with pm.Model() as model:
    a = pm.Normal('a', 3, 10)
    b = pm.Normal('b', 10, 5)
    c = a+b

How the c distribution is computed?

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#2

Technically speaking, c is a random variable, which follow a distribution that is the result of the convolution between a and b.

In practice, PyMC3 samples from a and b (a single realization of the random variable), and add the number together

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