Error Label with Python: encoding declaration in Unicode string (<string>, line 0)

Question

I get this error using Python while I'm trying to label a shapefile. The strange thing is that for other shapefiles the code works.

There is a table (relates.dbf) that has the data to be used for labelling and it has the fields: Schacht (string), Auswahl (short integer), max_Übers (double) and Max_Wieder (double).

The problem shouldn't be there.

NB: The SQL for this labelling class is [TN_UEB] > 0 and I use ArcGIS 10.3.1. The code is a variation of http://support.esri.com/technical-article/000012230

Any clues? What does it mean "line 0"! Where's the problem?

def FindLabel ([Name], [TN_UEB]):
  import arcpy

  key1 = [Name]
  key2 = "Schacht"
  key3 = "Auswahl"
  L =  "<FNT size = '10'><BOL>" + [Name] + "\n" +  " Ta = " + [TN_UEB] + " a" + "</BOL></FNT>" + "\n"
  L2 = "max_Übers"
  L3 = "Max_Wieder"
  myDataTable = r"P:\Duesseldorf\50009\FOG\Bestand_pz\Vergleich_Ergebnisse\KOSTRA_Auswertung\Variante_1_D_neuneu\relates.dbf"

  cur = arcpy.da.SearchCursor(myDataTable, [key2, L2, L3, key3])
  for row in cur:
    if str(key1) == str(row[0]) and row[3]>0:
      L = L + str(round(float(row[1]),1)) + " m" + "<SUP>"+"3"+"</SUP>" + " (T=" + str(round(float(row[2]),1)) + "a)" + "\n"
  return L

Answer 1

You can try adding the coding at the beginning of your script:

# coding: utf-8

In your script you can try to declare all strings with a u in front:

u'strings' 

This refferrs to Python 2, as for Python 3 Unicode is default, but maybe it's worth to give it a shot. (You didn't mention which Python version you are using.)