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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 add_country_locations(self, countries, locations=None, use_live=True):
 # type: (List[str], Optional[List[str]], bool) -> bool """Add a list of countries. If iso 3 codes are not provided, values are parsed and where they are valid country names, converted to iso 3 codes. If any country is already added, it is ignored. Args: countries (List[str]):
 list of countries to add locations (Optional[List[str]]):
 Valid locations list. Defaults to list downloaded from HDX. use_live (bool):
 Try to get use latest country data from web rather than file in package. Defaults to True. Returns: bool: True if all countries added or False if any already present. """

        allcountriesadded = True
        for country in countries:
            if not self.add_country_location(country, locations=locations, use_live=use_live):
                allcountriesadded = False
        return allcountriesadded