"""Some test interpreter lines for a demo

Get help or find out the type of any object by e.g.
help(a)
"""
5*3
1//2
1.0/2.0
a=5
b=5.0

#Lists can hold intgers, floats, strings, and *any* python objects
#(including more lists - you can have lists of lists)
#They can be indexed...
list_a = []
list_a.append(1)
list_b = [2.0]
list_clist_a + list_b
print(list_c)
print(list_c[0])

#Tuples are useful for moving multiple variables in to or out of functions, but 
#are "immutable" - you can't change their contents and have to create a new tuple
#to do so.
tuple_a = (1, 0.5)
tuple_b = ('one', 'half')
tuple_c = tuple_a + tuple_b
#Following doesn't work.
tuple_c[0]=9
#This shows how to get tuples in and out of functions...
def dummy():
    return 1,2.0

myvar = dummy()
dummy[0]
def printtwo(a,b):
    print(a)
    print(b)

two_things = (1,2.0)
printtwo(*two_things)

#Dictionaries are very neat ways of storing labelled un-structured data.
#They are compatible with json, a common modern format for storing
#structured data.
dict_a = {"one":1, "two":2}
dict_b = dict(three=3, four=4)
dict_a.update(dict_b)
dict_a['one']

#Finally... strings are like lists of characters.
str_a = "Hello"
str_b = "World."
str_a + " " + str_b
str_a += " "
str_a.__add__(str_b)