添加从具有函数定义的字符串生成 LaTeX 的功能

def get_latex_str( fn_def, identifiers: dict[str, str] | None = None, reduce_assignments: bool = False, use_math_symbols: bool = False, use_raw_function_name: bool = False, use_signature: bool = True, use_set_symbols: bool = False, ) -> str: """Obtains LaTeX description from the function's source.