instruction:
In this task you will be given a string that only contains single digit numbers spelled out. The input string will not contain spaces between the different numbers. Your task is to return the number that the string spells out. The string will spell out each digit of the number for example '1726' will be 'oneseventwosix' instead of 'one thousand seven hundred six'.
question:
sevenfoursevenfivethreeonefourfourfivesevenone
answer:
74753144571


question:
seveneighteightthreethreesevenseveneightseveneighttwoone
answer:
788337787821


question:
zeroeightoneseventwosixeightsevenzerosevenseven
answer:

08172687077