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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_to_scratch(file_mapping, dry_run=True):
 """Copy input files to scratch area """

        for key, value in file_mapping.items():
            if not os.path.exists(key):
                continue
            if dry_run:
                print ("copy %s %s" % (key, value))
            else:
                print ("copy %s %s" % (key, value))
                copyfile(key, value)

        return file_mapping