def project_config(self) -> Config:
        """Read-and-writable configuration dict for project settings"""
        config = Config(self.root / "pdm.toml")
        # TODO: for backward compatibility, remove this in the future
        if self.root.joinpath(".pdm.toml").exists():
            legacy_config = Config(self.root / ".pdm.toml").self_data
            config.update((k, v) for k, v in legacy_config.items() if k != "python.path")
        return config
Read-and-writable configuration dict for project settings
src/pdm/project/core.py