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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 get_user_group(self, user=None, group=None):
 """ Get the user and group information. Parameters user : str User name or user id (default is the `os.getuid()`). group : str Group name or group id (default is the group of `user`). Returns ------- user : pwd.struct_passwd User object. group : grp.struct_group Group object. """

        user = user or os.getuid()
        # Convert the information we have obtained to a user object
        try:
            try:
                user = pwd.getpwuid(int(user))
            except ValueError:
                user = pwd.getpwnam(user)
        except KeyError as ex:  # pragma: no cover
            self.logger.fatal("could not resolve user: %s", ex)
            raise

        # Get the group
        group = group or user.pw_gid
        try:
            try:
                group = grp.getgrgid(int(group))
            except ValueError:
                group = grp.getgrnam(group)
        except KeyError as ex:  # pragma: no cover
            self.logger.fatal("could not resolve group:%s", ex)
            raise

        return user, group