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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_asset(self, asset, asset_name, asset_type):
 """ Adds a asset to the Victim Valid asset_type: + PHONE + EMAIL + NETWORK + SOCIAL + WEB Args: asset: asset_name: asset_type: PHONE, EMAIL, NETWORK, SOCIAL, or WEB Returns: """

        if not self.can_update():
            self._tcex.handle_error(910, [self.type])

        if asset == 'PHONE':
            return self.tc_requests.add_victim_phone_asset(self.unique_id, asset_name)
        if asset == 'EMAIL':
            return self.tc_requests.add_victim_email_asset(self.unique_id, asset_name, asset_type)
        if asset == 'NETWORK':
            return self.tc_requests.add_victim_network_asset(self.unique_id, asset_name, asset_type)
        if asset == 'SOCIAL':
            return self.tc_requests.add_victim_social_asset(self.unique_id, asset_name, asset_type)
        if asset == 'WEB':
            return self.tc_requests.add_victim_web_asset(self.unique_id, asset_name)
        self._tcex.handle_error(
            925, ['asset_type', 'add_asset', 'asset_type', 'asset_type', asset_type]
        )
        return None