Updates to tutorial and run post codacy changes

tutorials/tutorial12/tutorial.ipynb

@@ -60,14 +60,14 @@
     "if IN_COLAB:\n",
     "  !pip install \"pina-mathlab\"\n",
     "\n",
+    "import torch\n",
+    "\n",
     "#useful imports\n",
     "from pina.problem import SpatialProblem, TimeDependentProblem\n",
     "from pina.equation import Equation, FixedValue\n",
     "from pina.domain import CartesianDomain\n",
-    "import torch\n",
     "from pina.operator import grad, laplacian\n",
-    "from pina import Condition\n",
-    "\n"
+    "from pina import Condition"
    ]
   },
   {

tutorials/tutorial12/tutorial.py

@@ -38,16 +38,16 @@ except:
 if IN_COLAB:
   get_ipython().system('pip install "pina-mathlab"')
 
+import torch
+
 #useful imports
 from pina.problem import SpatialProblem, TimeDependentProblem
 from pina.equation import Equation, FixedValue
 from pina.domain import CartesianDomain
-import torch
 from pina.operator import grad, laplacian
 from pina import Condition
 
 
-
 # In[2]: