Made a couple of tweaks to lazy translation docs.

This is essential when calls to these functions are located in code paths that

are executed at module load time.

As this is something that can easily happen when defining models (the

declarative notation of Django models is implemented in a way such that model

fields are actually class level attributes) this means you need to make sure to

use lazy translations in the following cases:

As this is something that can easily happen when defining models, forms and

model forms (the declarative notation Django offers for them is implemented in a

way such that their fields are actually class level attributes) this means you

need to make sure to use lazy translations in the following cases:

Model fields and relationship ``verbose_name`` and ``help_text`` option values

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Model fields and relationships ``verbose_name`` and ``help_text`` option values

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For example, to translate the help text of the *name* field in the following

model, do the following::

            return self.kind.type == MOUSE_TYPE

        is_mouse.short_description = _('Is it a mouse?')

Notes on translation in models

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Working with lazy translation objects

-------------------------------------

The result of a ``ugettext_lazy()`` call can be used wherever you would use a

unicode string (an object with type ``unicode``) in Python. If you try to use

    class MyThing(models.Model):

        name = models.CharField(help_text=_('This is the help text'))

Working with lazy translation objects

-------------------------------------

Using ``ugettext_lazy()`` and ``ungettext_lazy()`` to mark strings in models

and utility functions is a common operation. When you're working with these

objects elsewhere in your code, you should ensure that you don't accidentally

convert them to strings, because they should be converted as late as possible

(so that the correct locale is in effect). This necessitates the use of a

couple of helper functions.

(so that the correct locale is in effect). This necessitates the use of the

helper function described next.

Joining strings: string_concat()

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