<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_vocabulary(preprocess_output_dir, name):
 """Loads the vocabulary file as a list of strings. Args: preprocess_output_dir: Should contain the file CATEGORICAL_ANALYSIS % name. name: name of the csv column. Returns: List of strings. Raises: ValueError: if file is missing. """

  vocab_file = os.path.join(preprocess_output_dir, CATEGORICAL_ANALYSIS % name)
  if not file_io.file_exists(vocab_file):
    raise ValueError('File %s not found in %s' %
                     (CATEGORICAL_ANALYSIS % name, preprocess_output_dir))

  labels = python_portable_string(
      file_io.read_file_to_string(vocab_file)).split('\n')
  label_values = [x for x in labels if x]  # remove empty lines

  return label_values