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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_package_dependency(self, package_name, version):
 """ Add a package to the list of dependencies. :param package_name: The name of the package dependency :type package_name: str :param version: The (minimum) version of the package :type version: str """

        if not PEP440_VERSION_PATTERN.match(version):
            raise ValueError('Invalid Version: "{}"'.format(version))
        self.dependencies.add(PackageDependency(package_name, version))