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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 generate_file_name(self):
 """generate a suitable file name for the experiment"""

        if not self.project:
            raise UnderDefined("project name not given")

        out_data_dir = prms.Paths.outdatadir
        project_dir = os.path.join(out_data_dir, self.project)
        file_name = "cellpy_batch_%s.json" % self.name
        self.file_name = os.path.join(project_dir, file_name)