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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 package(self, output=None):
 """ Only build the package """

        # Make sure we're in a venv.
        self.check_venv()

        # force not to delete the local zip
        self.override_stage_config_setting('delete_local_zip', False)
        # Execute the prebuild script
        if self.prebuild_script:
            self.execute_prebuild_script()
        # Create the Lambda Zip
        self.create_package(output)
        self.callback('zip')
        size = human_size(os.path.getsize(self.zip_path))
        click.echo(click.style("Package created", fg="green", bold=True) + ": " + click.style(self.zip_path, bold=True) + " (" + size + ")")