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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 pg_ctl(self, cmd, *args, **kwargs):
 """Builds and executes pg_ctl command :returns: `!True` when return_code == 0, otherwise `!False`"""


        pg_ctl = [self._pgcommand('pg_ctl'), cmd]
        return subprocess.call(pg_ctl + ['-D', self._data_dir] + list(args), **kwargs) == 0