input: Write a function to create an instance of the "sru" class and call its "search" method to perform a search, passing in a query string and optionally specifying a collection name, start record number, maximum number of records to return, and record schema. The method should return a "response" object containing the results of the search. The response object can then be used to extract specific information from the search results, such as titles, creators, and subjects.
  
  
  def perform_search(query: str, collection: str = None, start_record: int = 1, max_records: int = 1, record_schema: str = None):
      instance = sru()
      response_obj = instance.search(query, collection, start_record, max_records, record_schema)
      return response_obj
  
  # Example test cases
  assert perform_search("keyword", "GGC", 1, 5).nr_of_records == 5
  assert len(perform_search("another keyword", "ANP", 1, 3).titles) == 3
  assert isinstance(perform_search("test query"), response)
  assert perform_search("empty query", start_record=2, max_records=0) == False
  
output: 
  def perform_search(query: str, collection: str = None, start_record: int = 1, max_records: int = 1, record_schema: str = None):
      instance = sru()
      response_obj = instance.search(query, collection, start_record, max_records, record_schema)
      return response_obj
  