for k, v in other.partial_variables.items():
                if k in partial_variables:
                    raise ValueError("Cannot have same variable partialed twice.")
                else:
                    partial_variables[k] = v
            return PromptTemplate(
                template=template,
                input_variables=input_variables,
                partial_variables=partial_variables,
                template_format="f-string",
                validate_template=validate_template,
            )
        elif isinstance(other, str):
            prompt = PromptTemplate.from_template(other)
            return self + prompt
        else:
            raise NotImplementedError(f"Unsupported operand type for +: {type(other)}")
    @property
    def _prompt_type(self) -> str:
        """Return the prompt type key."""
        return "prompt"
[docs]    def format(self, **kwargs: Any) -> str:
        """Format the prompt with the inputs.
        Args:
            kwargs: Any arguments to be passed to the prompt template.
        Returns:
            A formatted string.
        Example:
            .. code-block:: python
                prompt.format(variable1="foo")
        """
        kwargs = self._merge_partial_and_user_variables(**kwargs)
        return DEFAULT_FORMATTER_MAPPING[self.template_format](self.template, **kwargs)
    @root_validator()
    def template_is_valid(cls, values: Dict) -> Dict:
        """Check that template and input variables are consistent."""
        if values["validate_template"]:
            all_inputs = values["input_variables"] + list(values["partial_variables"])
            check_valid_template(
                values["template"], values["template_format"], all_inputs
            )
        elif values.get("template_format"):
            values["input_variables"] = [
                var
                for var in get_template_variables(
                    values["template"], values["template_format"]
                )