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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def now(format_string):
 """ Displays the date, formatted according to the given string. Uses the same format as PHP's ``date()`` function; see http://php.net/date for all the possible values. Sample usage:: It is {% now "jS F Y H:i" %} """

    from datetime import datetime
    from django.utils.dateformat import DateFormat
    return DateFormat(datetime.now()).format(self.format_string)