Python3: plugin code still has references to removed itertools.izip

itertools.izip was removed in Python3. References to it remain in the code:

blissadm@lid02eiger2lima:~/Git/Lima/applications/tango/python$ git grep izip
plugins/Bpm.py:    return itertools.izip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)
plugins/Memcached.py:#     return itertools.izip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)
plugins/PeakFinder.py:    return itertools.izip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)
plugins/Roi2Spectrum.py:    return itertools.izip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)

The suggested solution is to apply the patch in d9a29084:

diff --git a/plugins/RoiCounter.py b/plugins/RoiCounter.py
index 4c0eb12..ad06573 100644
--- a/plugins/RoiCounter.py
+++ b/plugins/RoiCounter.py
@@ -30,7 +30,7 @@ from Lima import Core
 from Lima.Server.plugins.Utils import getDataFromFile,BasePostProcess
 
 def grouper(n, iterable, padvalue=None):
-    return itertools.izip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)
+    return zip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)
 
 RoiCounterTask = Core.Processlib.Tasks.RoiCounterTask
 

Another alternative, which allows still using itertools.izip in Python2 (probably not worth), was applied in Lima-camera-simulator@c6fa7a57:

diff --git a/tango/Simulator.py b/tango/Simulator.py
index 0a08528..8220d57 100644
--- a/tango/Simulator.py
+++ b/tango/Simulator.py
@@ -26,13 +26,19 @@
 import itertools
 import PyTango
 
+# python3 compat
+try:
+    from itertools import izip as zip
+except ImportError:
+    pass
+
 from Lima.Server import AttrHelper
 
 from Lima import Core
 from Lima import Simulator as SimuMod
 
 def grouper(n, iterable, padvalue=None):
-    return itertools.izip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)
+    return zip(*[itertools.chain(iterable, itertools.repeat(padvalue, n-1))]*n)
 
 
 class Simulator(PyTango.Device_4Impl):

In any case, the solution should be uniform inside the repository, that is, for the following files:

blissadm@lid02eiger2lima:~/Git/Lima/applications/tango/python$ git grep 'def grouper'
plugins/Bpm.py:def grouper(n, iterable, padvalue=None):
plugins/Memcached.py:# def grouper(n, iterable, padvalue=None):
plugins/PeakFinder.py:def grouper(n, iterable, padvalue=None):
plugins/Roi2Spectrum.py:def grouper(n, iterable, padvalue=None):
plugins/RoiCounter.py:def grouper(n, iterable, padvalue=None):