The sentence you quoted ends a paragraph that begins with a sentences saying the same thing even more clearly.  "The execution of a function introduces a new symbol table used for the local variables of the function."  I think the ending sentence could be deleted as redundant.  Or it could be merged into the initial sentence with "When a function is called, the execution of that function ... ."  What do you think?

The me, the confusion of 'other function' is that it leaves open the possibility of 'same function' having a different result, as in languages with tail recursion conversion.  But this is not true of python, which cares nothing about the caller.