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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _parse_interfaces(self):
 """Scans the global config and returns the configured interfaces Returns: dict: A dict object that is intended to be merged into the resource dict. """

        interfaces = dict()
        names = re.findall(r'^interface (Po.+)$', self.config, re.M)
        for name in names:
            config = self.get_block('interface %s' % name)
            match = re.search(r'mlag (\d+)', config)
            if match:
                interfaces[name] = dict(mlag_id=match.group(1))
        return dict(interfaces=interfaces)