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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 _GetConfigValue(self, config_parser, section_name, value_name):
 """Retrieves a value from the config parser. Args: config_parser (ConfigParser):
 configuration parser. section_name (str):
 name of the section that contains the value. value_name (str):
 name of the value. Returns: object: configuration value or None if the value does not exists. """

    try:
      return config_parser.get(section_name, value_name)
    except configparser.NoOptionError:
      return None