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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 pkg_by_name(self, name):
 """ Return a single package that matches name. """

        pkgmatches = self.all_pkgs_by_name(name)
        if (len(pkgmatches) != 0):
            return self.all_pkgs_by_name(name)[-1]
        else:
            return None