[HowTo] Python's substring of a string workaround

In Python there is no dedicated function like "substring" (there is such a function in C#). In the following I have marked a workaround that retrieves the substring (the encoding in this particular case) of a super string that comes after "=" (equal sign):

 def fetchContent(self, url):
try:
fetchResult = urlfetch.fetch(url)
except:
return 'Exception: Not an URL'
if fetchResult.status_code == 200:
       encTypeRaw = fetchResult.headers['content-type']
       encStartIdx = encTypeRaw.find('=')
       encType = encTypeRaw[encStartIdx + 1:]
fetchResultContent = fetchResult.content
return fetchResultContent.decode(encType)
return 'Warning: URL could not be retrieved successfully'