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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 package to the distribution server. Bundle-style packages must be zipped prior to copying. Args: filename: Full path to file to upload. id_: ID of Package object to associate with, or -1 for new packages (default). """

        self._copy(filename, id_=id_, file_type=PKG_FILE_TYPE)