Streams chunks of a file located at given path starting at given offset.

    Args:
      filepath: A path to the file to stream.
      offset: An integer offset at which the file stream should start on.
      amount: An upper bound on number of bytes to read.

    Yields:
      `Chunk` instances.

def StreamFilePath(self, filepath, offset=0, amount=None):
    """Streams chunks of a file located at given path starting at given offset.

    Args:
      filepath: A path to the file to stream.
      offset: An integer offset at which the file stream should start on.
      amount: An upper bound on number of bytes to read.

    Yields:
      `Chunk` instances.
    """
    with open(filepath, "rb") as filedesc:
      for chunk in self.StreamFile(filedesc, offset=offset, amount=amount):
        yield chunk