Remove 'import *' in tutorial code and tests.

doc/extending/graphstructures.txt

@@ -74,12 +74,10 @@ This is what you would normally type:
 
 .. code-block:: python
 
-    from theano.tensor import *
-
     # create 3 Variables with owner = None
-    x = matrix('x')
-    y = matrix('y')
-    z = matrix('z')
+    x = T.matrix('x')
+    y = T.matrix('y')
+    z = T.matrix('z')
 
     # create 2 Variables (one for 'e', one intermediate for y*z)
     # create 2 Apply instances (one for '+', one for '*')
@@ -95,7 +93,7 @@ This is what you would type to build the graph explicitly:
 
 .. code-block:: python
 
-    from theano.tensor import *
+    from theano.tensor import add, mul, Apply, Variable, TensorType
 
     # Instantiate a type that represents a matrix of doubles
     float64_matrix = TensorType(dtype = 'float64',              # double

theano/tests/test_tutorial.py

@@ -903,20 +903,20 @@ class T_graphstructures(unittest.TestCase):
 
     def test_graphstructures_1(self):
 
-        from theano.tensor import *
-
-        x = dmatrix('x')
-        y = dmatrix('y')
+        x = T.dmatrix('x')
+        y = T.dmatrix('y')
         z = x + y
 
-        x = matrix('x')
-        y = matrix('y')
-        z = matrix('z')
+        x = T.matrix('x')
+        y = T.matrix('y')
+        z = T.matrix('z')
 
         # create 2 Variables (one for 'e', one intermediate for y*z)
         # create 2 Apply instances (one for '+', one for '*')
         e = x + y * z
 
+        from theano.tensor import add, mul, Apply, Variable, TensorType
+
         # Instantiate a type that represents a matrix of doubles
         float64_matrix = TensorType(dtype = 'float64',              # double
                                     broadcastable = (False, False)) # matrix