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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 _GenerateStorageFileName(self):
 """Generates a name for the storage file. The result use a timestamp and the basename of the source path. Returns: str: a filename for the storage file in the form <time>-<source>.plaso Raises: BadConfigOption: raised if the source path is not set. """

    if not self._source_path:
      raise errors.BadConfigOption('Please define a source (--source).')

    timestamp = datetime.datetime.now()
    datetime_string = timestamp.strftime('%Y%m%dT%H%M%S')

    source_path = os.path.abspath(self._source_path)

    if source_path.endswith(os.path.sep):
      source_path = os.path.dirname(source_path)

    source_name = os.path.basename(source_path)

    if not source_name or source_name in ('/', '\\'):
      # The user passed the filesystem's root as source
      source_name = 'ROOT'

    return '{0:s}-{1:s}.plaso'.format(datetime_string, source_name)