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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 _get_db_options(args):
 """Parse through a command line of arguments to over-ride the values in the users .dbrc file. If no user name is given then the environment variable $USERNAME is used. If $USERNAME is not defined then prompt for input. """

    import optik, getpass,sys
    from optik import OptionParser
    parser=OptionParser()
    parser.add_option("-d","--database",
                  action="store", type="string", dest="database",
                  default="cfht",
                  help="Name of the SYBASE database containing TABLE",
                  metavar="FILE")
    parser.add_option("-u","--user",
                  action="store", type="string", dest="user",
                  default=getpass.getuser(),
                  help="User name to access db with",
                  metavar="USER")
    (opt, unused_args) = parser.parse_args(args)
    return opt.database,opt.user,unused_args