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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 extra_html_properties(self, prefix=None, postfix=None, template_type=None):
        '''
        Return extra html properties to allow individual apps to be styled separately.

        The content returned from this function is injected unescaped into templates.
        '''

        prefix = prefix if prefix else "django-plotly-dash"

        post_part = "-%s" % postfix if postfix else ""
        template_type = template_type if template_type else "iframe"

        slugified_id = self.slugified_id()

        return "%(prefix)s %(prefix)s-%(template_type)s %(prefix)s-app-%(slugified_id)s%(post_part)s" % {'slugified_id':slugified_id,
                                                                                                         'post_part':post_part,
                                                                                                         'template_type':template_type,
                                                                                                         'prefix':prefix,
                                                                                                        }