import inspect
import sys


class Structure:
    _fields = ()

    def __repr__(self):
        args = map(lambda field: f"{field}={getattr(self, field)!r}", self._fields)
        return f"{type(self).__name__}({', '.join(args)})"

    def __setattr__(self, name, value):
        if name in self._fields or name[0] == '_':
            super().__setattr__(name, value)
        else:
            raise AttributeError(f"No attribute {name}")

    @classmethod
    def create_init(cls):
        code = f'def __init__(self, {", ".join(cls._fields)}):\n'
        for name in cls._fields:
            code += f'    self.{name} = {name}\n'
        locs = {}
        exec(code, locs)
        cls.__init__ = locs['__init__']