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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ConfigureDatastore(config):
 """Guides the user through configuration of the datastore."""

  print("\n\n-=GRR Datastore=-\n"
        "For GRR to work each GRR server has to be able to communicate with\n"
        "the datastore. To do this we need to configure a datastore.\n")

  existing_datastore = grr_config.CONFIG.Get("Datastore.implementation")

  if not existing_datastore or existing_datastore == "FakeDataStore":
    ConfigureMySQLDatastore(config)
    return

  print("Found existing settings:\n  Datastore: %s" % existing_datastore)
  if existing_datastore == "SqliteDataStore":
    set_up_mysql = RetryBoolQuestion(
        "The SQLite datastore is no longer supported. Would you like to\n"
        "set up a MySQL datastore? Answering 'no' will abort config "
        "initialization.", True)
    if set_up_mysql:
      print("\nPlease note that no data will be migrated from SQLite to "
            "MySQL.\n")
      ConfigureMySQLDatastore(config)
    else:
      raise ConfigInitError()
  elif existing_datastore == "MySQLAdvancedDataStore":
    print("  MySQL Host: %s\n  MySQL Port: %s\n  MySQL Database: %s\n"
          "  MySQL Username: %s\n" %
          (grr_config.CONFIG.Get("Mysql.host"),
           grr_config.CONFIG.Get("Mysql.port"),
           grr_config.CONFIG.Get("Mysql.database_name"),
           grr_config.CONFIG.Get("Mysql.database_username")))
    if grr_config.CONFIG.Get("Mysql.client_key_path"):
      print("  MySQL client key file: %s\n"
            "  MySQL client cert file: %s\n"
            "  MySQL ca cert file: %s\n" %
            (grr_config.CONFIG.Get("Mysql.client_key_path"),
             grr_config.CONFIG.Get("Mysql.client_cert_path"),
             grr_config.CONFIG.Get("Mysql.ca_cert_path")))

    if not RetryBoolQuestion("Do you want to keep this configuration?", True):
      ConfigureMySQLDatastore(config)