diff --git a/doc/examples/mupp/sigmaSC-vs-temp-py.txt b/doc/examples/mupp/sigmaSC-vs-temp-py.txt
index d970fd1ee..41059e2a1 100644
--- a/doc/examples/mupp/sigmaSC-vs-temp-py.txt
+++ b/doc/examples/mupp/sigmaSC-vs-temp-py.txt
@@ -6,24 +6,27 @@ loadPath ./
 load YBCO-40nm-FC-E3p8keV-B10mT-Tscan.db  # collection 0
 load YBCO-40nm-FC-E3p8keV-B150mT-Tscan.db # collection 1
 
-# B=10mT
-select 0
+# declare the python variables (one block for all of them, see below)
 var SigmaSC_10 = python
 var SigmaSC_10Err = python
-<python>
-import numpy as np
-SigmaSC_10 = np.sqrt(abs(np.array(Sigma)**2-0.11**2))
-SigmaSC_10Err = np.sqrt((np.array(Sigma)*np.array(SigmaErr))**2+(0.11*0.0025)**2)/np.array(SigmaSC_10)
-</python>
-
-# B=150mT
-select 1
 var SigmaSC_150 = python
 var SigmaSC_150Err = python
+
+# a single python block can serve several collections: address each one
+# explicitly via coll[]/collErr[], either by index (coll[0], B=10mT) or by name
+# (coll['...Tscan.db'], B=150mT). Both addressing modes are shown here.
 <python>
 import numpy as np
-SigmaSC_150 = np.sqrt(abs(np.array(Sigma)**2-0.075**2))
-SigmaSC_150Err = np.sqrt((np.array(Sigma)*np.array(SigmaErr))**2+(0.075*0.0025)**2)/np.array(SigmaSC_150)
+# B=10mT -> collection 0, addressed by index
+s10  = np.array(coll[0]['Sigma'])
+se10 = np.array(collErr[0]['Sigma'])
+SigmaSC_10    = np.sqrt(abs(s10**2-0.11**2))
+SigmaSC_10Err = np.sqrt((s10*se10)**2+(0.11*0.0025)**2)/SigmaSC_10
+# B=150mT -> collection 1, addressed by name
+s150  = np.array(coll['YBCO-40nm-FC-E3p8keV-B150mT-Tscan.db']['Sigma'])
+se150 = np.array(collErr['YBCO-40nm-FC-E3p8keV-B150mT-Tscan.db']['Sigma'])
+SigmaSC_150    = np.sqrt(abs(s150**2-0.075**2))
+SigmaSC_150Err = np.sqrt((s150*se150)**2+(0.075*0.0025)**2)/SigmaSC_150
 </python>
 
 # link variables to collections