text: # -*- coding: utf-8 -*-
  from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  
  import csv
  import numpy as np
  import os
  import sys
  
  from observations.util import maybe_download_and_extract
  
  
  def leukemia(path):
    """Acute Myelogenous Leukemia survival data
  
    Survival in patients with Acute Myelogenous Leukemia. The question at
    the time was whether the standard course of chemotherapy should be
    extended ('maintainance') for additional cycles.
  
    time:
  
    survival or censoring time
  
    status:
  
    censoring status
  
    x:
  
    maintenance chemotherapy given? (factor)
  
    Rupert G. Miller (1997), *Survival Analysis*. John Wiley & Sons. ISBN:
  
    Args:
  
      path: str.
        Path to directory which either stores file or otherwise file will
        be downloaded and extracted there.
        Filename is `leukemia.csv`.
  
    Returns:
  
      Tuple of np.ndarray `x_train` with 23 rows and 3 columns and
      dictionary `metadata` of column headers (feature names).
    """
    import pandas as pd
    path = os.path.expanduser(path)
    filename = 'leukemia.csv'
    if not os.path.exists(os.path.join(path, filename)):
      url = 'http://dustintran.com/data/r/survival/leukemia.csv'
      maybe_download_and_extract(path, url,
                                 save_file_name='leukemia.csv',
                                 resume=False)
  
    data = pd.read_csv(os.path.join(path, filename), index_col=0,
                       parse_dates=True)
    x_train = data.values
    metadata = {'columns': data.columns}
    return x_train, metadata
  