def load_pyproject_toml(self):<EOL>
pep517_data = load_pyproject_toml(<EOL>self.use_pep517,<EOL>self.pyproject_toml,<EOL>self.setup_py,<EOL>str(self)<EOL>)<EOL>if pep517_data is None:<EOL><INDENT>self.use_pep517 = False<EOL><DEDENT>else:<EOL><INDENT>self.use_pep517 = True<EOL>requires, backend, check = pep517_data<EOL>self.requirements_to_check = check<EOL>self.pyproject_requires = requires<EOL>self.pep517_backend = Pep517HookCaller(self.setup_py_dir, backend)<EOL>self.spin_message = "<STR_LIT>"<EOL>def runner(cmd, cwd=None, extra_environ=None):<EOL><INDENT>with open_spinner(self.spin_message) as spinner:<EOL><INDENT>call_subprocess(<EOL>cmd,<EOL>cwd=cwd,<EOL>extra_environ=extra_environ,<EOL>show_stdout=False,<EOL>spinner=spinner<EOL>)<EOL><DEDENT>self.spin_message = "<STR_LIT>"<EOL><DEDENT>self.pep517_backend._subprocess_runner = runner<EOL><DEDENT>
Load the pyproject.toml file.

        After calling this routine, all of the attributes related to PEP 517
        processing for this requirement have been set. In particular, the
        use_pep517 attribute can be used to determine whether we should
        follow the PEP 517 or legacy (setup.py) code path.