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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 addUser(self, username, password, firstname, lastname, email, role):
 """adds a user to the invitation list"""

        self._invites.append({
            "username":username,
            "password":password,
            "firstname":firstname,
            "lastname":lastname,
            "fullname":"%s %s" % (firstname, lastname),
            "email":email,
            "role":role
        })