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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 authorization_url(self, client_id, redirect_uri, approval_prompt='auto', scope=None, state=None):
 """ Get the URL needed to authorize your application to access a Strava user's information. :param client_id: The numeric developer client id. :type client_id: int :param redirect_uri: The URL that Strava will redirect to after successful (or failed) authorization. :type redirect_uri: str :param approval_prompt: Whether to prompt for approval even if approval already granted to app. Choices are 'auto' or 'force'. (Default is 'auto') :type approval_prompt: str :param scope: The access scope required. Omit to imply "public". Valid values are 'read', 'read_all', 'profile:read_all', 'profile:write', 'profile:read_all', 'activity:read_all', 'activity:write' :type scope: str :param state: An arbitrary variable that will be returned to your application in the redirect URI. :type state: str :return: The URL to use for authorization link. :rtype: str """

        return self.protocol.authorization_url(client_id=client_id,
                                               redirect_uri=redirect_uri,
                                               approval_prompt=approval_prompt,
                                               scope=scope, state=state)