input: Write a function called `kb_sru_search` that creates an instance of the "sru" class and calls its "search" method to perform a search using the KB SRU API. The function should take a query string, an optional collection name, an optional start record number, an optional maximum number of records to return, and an optional record schema. The function should return a "response" object containing the search results. If the search results are empty, the function should return False.
  
  assert kb_sru_search("python API", "GGC", 1, 10, "dcx") != False
  assert kb_sru_search("unknown query", "DPO", 1, 10, "ddd") == False
  assert kb_sru_search("API", "BYVANCK", 1, 5, "dcx") != False
  assert kb_sru_search("API") == False
output: def kb_sru_search(query, collection=None, start=None, max_records=None, schema=None):
      sru_instance = sru()
      response = sru_instance.search(query, collection, start, max_records, schema)
      if response.is_empty():
          return False
      return response