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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 get_database_info(db_uri):
 """Returns TBContext fields relating to SQL database. Args: db_uri: A string URI expressing the DB file, e.g. "sqlite:~/tb.db". Returns: A tuple with the db_module and db_connection_provider TBContext fields. If db_uri was empty, then (None, None) is returned. Raises: ValueError: If db_uri scheme is not supported. """

  if not db_uri:
    return None, None
  scheme = urlparse.urlparse(db_uri).scheme
  if scheme == 'sqlite':
    return sqlite3, create_sqlite_connection_provider(db_uri)
  else:
    raise ValueError('Only sqlite DB URIs are supported now: ' + db_uri)