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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 update_user(self, user_is_artist="", artist_level="", artist_specialty="", real_name="", tagline="", countryid="", website="", bio=""):
 """Update the users profile information :param user_is_artist: Is the user an artist? :param artist_level: If the user is an artist, what level are they :param artist_specialty: If the user is an artist, what is their specialty :param real_name: The users real name :param tagline: The users tagline :param countryid: The users location :param website: The users personal website :param bio: The users bio """




        if self.standard_grant_type is not "authorization_code":
            raise DeviantartError("Authentication through Authorization Code (Grant Type) is required in order to connect to this endpoint.")

        post_data = {}

        if user_is_artist:
            post_data["user_is_artist"] = user_is_artist

        if artist_level:
            post_data["artist_level"] = artist_level

        if artist_specialty:
            post_data["artist_specialty"] = artist_specialty

        if real_name:
            post_data["real_name"] = real_name

        if tagline:
            post_data["tagline"] = tagline

        if countryid:
            post_data["countryid"] = countryid

        if website:
            post_data["website"] = website

        if bio:
            post_data["bio"] = bio

        response = self._req('/user/profile/update', post_data=post_data)

        return response['success']