
The online document, Python GTK+ 3 Tutorial 1.0 documentation, gives an introduction to writing GTK+ 3 applications in Python.
link: http://python-gtk-3-tutorial.readthedocs.org/

HelloString = "Hello Python!"
print(HelloString)
print("Python exercise: Slicing Strings")
print (HelloString[2:10]) #from index 2 to 10-1
print (HelloString[2:]) #from index 2 to end
print (HelloString[:10]) #from begin to 10-1
print (HelloString[::3]) #every 3 characters
print (HelloString[::-1]) #every characters in reverse order

HelloString = "Python!"
print(HelloString)
StringLen = len(HelloString)
print("String Length: " + str(StringLen))
print("Print in normal order")
for i in range(0, StringLen):
print(HelloString[i])
print("Print in reverse order, negative indexing")
for i in range(1, StringLen+1):
print(HelloString[-i])

