text: Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
  ### Context:
  CREATE TABLE CMI_cross_references (source_system_code VARCHAR)
  ### Question:
  How many different source system code for the cmi cross references are there?
  ### Answer:
  SELECT COUNT(DISTINCT source_system_code) FROM CMI_cross_references