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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 save_account(self, account: Account) -> None: """ Account was saved. """

        person = account.person
        if self._primary_group == 'institute':
            lgroup = self._get_group(person.institute.group.name)
        elif self._primary_group == 'default_project':
            if account.default_project is None:
                lgroup = self._get_group(self._default_primary_group)
            else:
                lgroup = self._get_group(account.default_project.group.name)
        else:
            raise RuntimeError("Unknown value of PRIMARY_GROUP.")

        if account.default_project is None:
            default_project = "none"
        else:
            default_project = account.default_project.pid

        try:
            luser = self._get_account(account.username)
            changes = changeset(luser, {})
            new_user = False
        except ObjectDoesNotExist:
            new_user = True
            luser = self._account_class()
            changes = changeset(luser, {
                'uid': account.username
            })

        changes = changes.merge({
            'gidNumber': lgroup['gidNumber'],
            'givenName': person.first_name,
            'sn': person.last_name,
            'telephoneNumber': _str_or_none(person.telephone),
            'mail': _str_or_none(person.email),
            'title': _str_or_none(person.title),
            'o': person.institute.name,
            'cn': person.full_name,
            'default_project': default_project,
            'loginShell': account.shell,
            'locked': account.is_locked()
        })
        save(changes, database=self._database)

        if new_user:
            # add all groups
            for group in account.person.groups.all():
                self.add_account_to_group(account, group)