Merge pull request #5463 from PaddlePaddle/uciHousingModel

uci_housing.py can download the trained model automatically.

python/paddle/v2/dataset/uci_housing.py

@@ -22,6 +22,7 @@ parse training set and test set into paddle reader creators.
 import numpy as np
 import os
 import paddle.v2.dataset.common
+from paddle.v2.parameters import Parameters
 
 __all__ = ['train', 'test']
 
@@ -34,7 +35,8 @@ feature_names = [
 
 UCI_TRAIN_DATA = None
 UCI_TEST_DATA = None
-
+URL_MODEL = 'https://github.com/PaddlePaddle/book/raw/develop/01.fit_a_line/fit_a_line.tar'
+MD5_MODEL = '52fc3da8ef3937822fcdd87ee05c0c9b'
 
 def feature_range(maximums, minimums):
     import matplotlib
@@ -111,6 +113,13 @@ def test():
     return reader
 
 
+def model():
+    tar_file = paddle.v2.dataset.common.download(URL_MODEL, 'fit_a_line.tar', MD5_MODEL)
+    with open(tar_file, 'r') as f:
+        parameters = Parameters.from_tar(f)
+    return parameters
+
+
 def fetch():
     paddle.v2.dataset.common.download(URL, 'uci_housing', MD5)