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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 with_wget(url_dict=None, target_file=None):
 """ Decorate a project class with wget-based version information. This adds two attributes to a project class: - A `versions` method that returns a list of available versions for this project. - A `repository` attribute that provides a repository string to download from later. We use the `git rev-list` subcommand to list available versions. Args: url_dict (dict):
 A dictionary that assigns a version to a download URL. target_file (str):
 An optional path where we should put the clone. If unspecified, we will use the `SRC_FILE` attribute of the decorated class. """


    def wget_decorator(cls):
        def download_impl(self):
            """Download the selected version from the url_dict value."""
            t_file = target_file if target_file else self.SRC_FILE
            t_version = url_dict[self.version]
            Wget(t_version, t_file)

        @staticmethod
        def versions_impl():
            """Return a list of versions from the url_dict keys."""
            return list(url_dict.keys())

        cls.versions = versions_impl
        cls.download = download_impl
        return cls

    return wget_decorator