The piece is almost entirely in A Major. The first eight measures serve as the expository section: two parallel, and nearly identical phrases that each end in a half cadence. I’m wondering if this is enough to call it a parallel symmetric period, but since there is no real sense of finality without an authentic cadence, I would have to call it a phrase group.
The developmental section occurs from measures 9 through 20: The piece is not as tonally stable since it modulates to E Major, as seen in the IAC in measure12 to end the first phrase. It modulates back to A Major and ends in a PAC in measure 20. This section could be arguably a contrasting, asymmetrical period with the antecedent phrase from measure 9 through 12, and the consequent phrase from measures 13 to 20.
The last section, from measures 21 to 29, serves as a terminative section with no clear cadences. These last measures firmly establish the A Major key.
All three of these sections have clear structural divisions with a double bar line after measure 8 and a repeat bar lines separating the middle developmental section from the rest.