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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 copy_pkg(self, filename, id_=-1):
 """Copy a pkg, dmg, or zip to all repositories. Args: filename: String path to the local file to copy. id_: Integer ID you wish to associate package with for a JDS or CDP only. Default is -1, which is used for creating a new package object in the database. """

        for repo in self._children:
            repo.copy_pkg(filename, id_)