I would like to receive a response that includes a detailed explanation of the process of photosynthesis, but with a few specific constraints. The response should contain at least 3 placeholders represented by square brackets, such as [chlorophyll]. Additionally, the response must have 2 sections. Mark the beginning of each section with SECTION X, such as: SECTION 1. Finally, at the end of your response, please explicitly add a postscript starting with P.S.

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