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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 copy_submission_to_destination(self, src_filename, dst_subdir, submission_id):
 """Copies submission to target directory. Args: src_filename: source filename of the submission dst_subdir: subdirectory of the target directory where submission should be copied to submission_id: ID of the submission, will be used as a new submission filename (before extension) """


    extension = [e for e in ALLOWED_EXTENSIONS if src_filename.endswith(e)]
    if len(extension) != 1:
      logging.error('Invalid submission extension: %s', src_filename)
      return
    dst_filename = os.path.join(self.target_dir, dst_subdir,
                                submission_id + extension[0])
    cmd = ['gsutil', 'cp', src_filename, dst_filename]
    if subprocess.call(cmd) != 0:
      logging.error('Can\'t copy submission to destination')
    else:
      logging.info('Submission copied to: %s', dst_filename)