set a timeout on socket connections (8 s) (nilearn#2461)

* set a timeout on socket connections (8 s)

examples/07_advanced/plot_ica_neurovault.py

@@ -39,11 +39,15 @@
 print("Fetching Neurovault images; "
       "if you haven't downloaded any Neurovault data before "
       "this will take several minutes.")
-nv_data = fetch_neurovault(max_images=80, fetch_neurosynth_words=True)
+nv_data = fetch_neurovault(max_images=30, fetch_neurosynth_words=True)
 
 images = nv_data['images']
 term_weights = nv_data['word_frequencies']
 vocabulary = nv_data['vocabulary']
+if term_weights is None:
+    term_weights = np.ones((len(images), 2))
+    vocabulary = np.asarray(
+        ["Neurosynth is down", "Please try again later"])
 
 # Clean and report term scores
 term_weights[term_weights < 0] = 0
@@ -103,7 +107,7 @@
 # We use a very small number of components as we have downloaded only 80
 # images. For better results, increase the number of images downloaded
 # and the number of components
-n_components = 16
+n_components = 8
 fast_ica = FastICA(n_components=n_components, random_state=0)
 ica_maps = fast_ica.fit_transform(X.T).T
 

nilearn/datasets/utils.py

@@ -14,9 +14,12 @@
 import sys
 import tarfile
 import urllib
+import socket
 import warnings
 import zipfile
 
+socket.setdefaulttimeout(8)
+
 
 def md5_hash(string):
     m = hashlib.md5()