[IMP] Added documenation in dates.py.
[IMP] Added documenation in dates.py.

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extra : convert_revision : nicolas.vanhoren%40openerp.com-20110511145119-l4fpcd8mzwntta19


havt/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web,akretion/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web