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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 AppendContent(self, src_fd):
 """Create new blob hashes and append to BlobImage. We don't support writing at arbitrary file offsets, but this method provides a convenient way to add blobs for a new file, or append content to an existing one. Args: src_fd: source file handle open for read Raises: IOError: if blob has already been finalized. """

    while 1:
      blob = src_fd.read(self.chunksize)
      if not blob:
        break

      blob_id = data_store.BLOBS.WriteBlobWithUnknownHash(blob)
      self.AddBlob(blob_id, len(blob))

    self.Flush()