"Variable variable name" or "variable lvalue"

[mfglinux]

Hello to everybody

I would like to know how to declare in python a "variable name" that
it is in turn a variable
In bash shell I would wrote sthg like:

for x in `seq 1 3`
do
  M$i=Material(x)  #Material is a python class
done

Why I need this? Cause I have a python module that obliges me to build
a variable called Period, which should have a variable name of
summands (depends on the value of x)

#Let's say x=3, then Period definition is
Period=Slab(Material1(12.5)+Material2(25)+Material3(12.5)) #Slab is a
python class

I dont know how to automatize last piece of code for any x

thank you

Marcos