qiskit/transpiler/passmanager.py
def _join_options(self, passset_options):
        """Set the options of each passset, based on precedence rules:
        passset options (set via ``PassManager.append()``) override
        passmanager options (set via ``PassManager.__init__()``), which override Default.
        .
        """
        default = {'ignore_preserves': False,  # Ignore preserves for this pass
                   'ignore_requires': False,  # Ignore requires for this pass
                   'max_iteration': 1000}  # Maximum allowed iteration on this pass

        passmanager_level = {k: v for k, v in self.passmanager_options.items() if v is not None}
        passset_level = {k: v for k, v in passset_options.items() if v is not None}
        return {**default, **passmanager_level, **passset_level}
def _join_options(self, passset_options):
        """Set the options of each passset, based on precedence rules:
        passset options (set via ``PassManager.append()``) override
        passmanager options (set via ``PassManager.__init__()``), which override Default.
        .
        """
        default = {'ignore_preserves': False,  # Ignore preserves for this pass
                   'ignore_requires': False,  # Ignore requires for this pass
                   'max_iteration': 1000}  # Maximum allowed iteration on this pass

        passmanager_level = {k: v for k, v in self.passmanager_options.items() if v is not None}
        passset_level = {k: v for k, v in passset_options.items() if v is not None}
        return {**default, **passmanager_level, **passset_level}
Set the options of each passset, based on precedence rules:
        passset options (set via ``PassManager.append()``) override
        passmanager options (set via ``PassManager.__init__()``), which override Default.
        .