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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 add_user(self, workspace, params={}, **options):
 """The user can be referenced by their globally unique user ID or their email address. Returns the full user record for the invited user. Parameters workspace : {Id} The workspace or organization to invite the user to. [data] : {Object} Data for the request - user : {String} An identifier for the user. Can be one of an email address, the globally unique identifier for the user, or the keyword `me` to indicate the current user making the request. """

        path = "/workspaces/%s/addUser" % (workspace)
        return self.client.post(path, params, **options)