Printing a list using python

Question

I have a list compiled from excel cells, using python - say listlist. Each element in the cell/list is in unicode. When I print the list as

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Answer 1

when you are printing a list, python prints a representation of the list.

the default representation of a list is to print an opening square brackets ([), then the representation of each element separated by a comma (,), the a closing square bracket (]). (to be precise the representation of an object is what is returned when calling its __repr__() member). note that the default representation of a unicode string is u'...'.

now, when you are printing a string, you are not printing the representation of the string, you are printing the string (the value returned by calling the __str__() member). and the string does not include formatting charaters like unicode flags, quotes, etc...

Answer 2

There are two ways to turn a Python value into a string str and repr (and their equivalent class methods __str__ and __repr__). The difference comes from these two functions. From the Python tutorial:

The str() function is meant to return representations of values which are fairly human-readable, while repr() is meant to generate representations which can be read by the interpreter (or will force a SyntaxError if there is not equivalent syntax).

The print statement calls str on the object you pass in, but the list's __str__ method calls repr on it's values. The values of your list are unicode strings. In human readable form the fact it's unicode is irrelevent, so you don't get a u, or even quote marks. In computer readable form it is important, so the u is included.

Answer 3

When printing the list, it shows each object within the list using the object's __repr__

When printing the object alone, it uses the object's __str__

Answer 4

This is because print list is equivalent to

print "[", ", ".join(repr(i) for i in list), "]"

repr(s) is u"blabla" for a unicode string while print s prints only blabla.