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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_connect(dbSystem,db,user,password):
 """Create a connection to the database specified on the command line """

    if dbSystem=='SYBASE':
        import Sybase    
        try:
            dbh = Sybase.connect(dbSystem,
                                 user,
                                 password,
                                 database=db )
        except:
            dbh=None
    elif dbSystem=='MYSQL':
        import MySQLdb
        try:
            dbh = MySQLdb.connect(user=user,
                                  passwd=password,
                                  db=db ,
                                  host='gimli')
        except:
            dbh=None
            
    return dbh