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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 user(self, user):
 """ Sets the user of this WebCredentials. The name of the account to login to. :param user: The user of this WebCredentials. :type: str """

        if user is None:
            raise ValueError("Invalid value for `user`, must not be `None`")
        if user is not None and len(user) > 1024:
            raise ValueError("Invalid value for `user`, length must be less than or equal to `1024`")

        self._user = user