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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 tags(self, resource_id=None):
 """Tag endpoint for this resource with optional tag name. This method will set the resource endpoint for working with Tags. The HTTP GET method will return all tags applied to this resource or if a resource id (tag name) is provided it will return the provided tag if it has been applied, which could be useful to verify a tag is applied. The provided resource_id (tag) can be applied to this resource using the HTTP POST method. The HTTP DELETE method will remove the provided tag from this resource. **Example Endpoints URI's** | HTTP Method | API Endpoint URI's | +==============+============================================================+ | GET | /v2/groups/{resourceType}/{uniqueId}/tags | | GET | /v2/groups/{resourceType}/{uniqueId}/tags/{resourceId} | | GET | /v2/indicators/{resourceType}/{uniqueId}/tags | | GET | /v2/indicators/{resourceType}/{uniqueId}/tags/{resourceId} | | DELETE | /v2/groups/{resourceType}/{uniqueId}/tags/{resourceId} | | DELETE | /v2/indicators/{resourceType}/{uniqueId}/tags/{resourceId} | | POST | /v2/groups/{resourceType}/{uniqueId}/tags/{resourceId} | | POST | /v2/indicators/{resourceType}/{uniqueId}/tags/{resourceId} | Args: resource_id (Optional [string]):
 The resource id (tag name). """

        resource = self.copy()
        resource._request_entity = 'tag'
        resource._request_uri = '{}/tags'.format(resource._request_uri)
        if resource_id is not None:
            resource._request_uri = '{}/{}'.format(
                resource._request_uri, self.tcex.safetag(resource_id)
            )
        return resource