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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 get_content(self, page, language, ctype, language_fallback=False):
 """Gets the latest content string for a particular page, language and placeholder. :param page: the concerned page object. :param language: the wanted language. :param ctype: the content type. :param language_fallback: fallback to another language if ``True``. """

        if page is None:
            page = fake_page

        if " " in ctype:
            raise ValueError("Ctype cannot contain spaces.")
        if not language:
            language = settings.PAGE_DEFAULT_LANGUAGE

        frozen = int(bool(page.freeze_date))
        key = self.PAGE_CONTENT_DICT_KEY % (page.id, ctype, frozen)

        # Spaces do not work with memcache
        key = key.replace(' ', '-')

        if page._content_dict is None:
            page._content_dict = dict()
        if page._content_dict.get(key, None):
            content_dict = page._content_dict.get(key)
        else:
            content_dict = cache.get(key)

        # fill a dict object for each language, that will create
        # P * L queries.
        # L == number of language, P == number of placeholder in the page.
        # Once generated the result is cached.
        if not content_dict:
            content_dict = {}
            for lang in settings.PAGE_LANGUAGES:
                try:
                    content = self.get_content_object(page, lang[0], ctype)
                    content_dict[lang[0]] = content.body
                except self.model.DoesNotExist:
                    content_dict[lang[0]] = ''
            page._content_dict[key] = content_dict
            cache.set(key, content_dict)

        if language in content_dict and content_dict[language]:
            return content_dict[language]

        if language_fallback:
            for lang in settings.PAGE_LANGUAGES:
                if lang[0] in content_dict and content_dict[lang[0]]:
                    return content_dict[lang[0]]
        return ''