Install script strange characters

Hi,
why in install script (MEGAN_Community_unix_6_21_1.sh) are some strange symbols on the end?
Is it some binary code inside shell script?
What does it do?

exampleFromInstallScript
[...]   
returnCode=$return_code
cd "$old_pwd"
if [ ! "W $INSTALL4J_KEEP_TEMP" = "W yes" ]; then
  rm -R -f "$sfx_dir_name"
fi
exit $returnCode
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yes, the install script should not be edited, it contains both text and code.