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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 _determine_branch_locations(self, other_services):
 """Determine the branch locations for the other services. Determine if the local branch being tested is derived from its stable or next (dev) branch, and based on this, use the corresonding stable or next branches for the other_services."""


        self.log.info('OpenStackAmuletDeployment:  determine branch locations')

        # Charms outside the ~openstack-charmers
        base_charms = {
            'mysql': ['trusty'],
            'mongodb': ['trusty'],
            'nrpe': ['trusty', 'xenial'],
        }

        for svc in other_services:
            # If a location has been explicitly set, use it
            if svc.get('location'):
                continue
            if svc['name'] in base_charms:
                # NOTE: not all charms have support for all series we
                #       want/need to test against, so fix to most recent
                #       that each base charm supports
                target_series = self.series
                if self.series not in base_charms[svc['name']]:
                    target_series = base_charms[svc['name']][-1]
                svc['location'] = 'cs:{}/{}'.format(target_series,
                                                    svc['name'])
            elif self.stable:
                svc['location'] = 'cs:{}/{}'.format(self.series,
                                                    svc['name'])
            else:
                svc['location'] = 'cs:~openstack-charmers-next/{}/{}'.format(
                    self.series,
                    svc['name']
                )

        return other_services