$ ninja -C build/
ninja: Entering directory `build/'
[1/151] Generating src/common/textevents with a custom command
FAILED: [code=127] src/common/textevents.h src/common/textenums.h 
/home/neel/Projects/hexchat/src/common/make-te.py ../src/common/textevents.in src/common/textevents.h src/common/textenums.h
/usr/bin/env: ‘python3\r’: No such file or directory
/usr/bin/env: use -[v]S to pass options in shebang lines
[2/151] Generating plugins/perl/hexchat-perl-header with a custom command
FAILED: [code=127] plugins/perl/hexchat.pm.h 
/home/neel/Projects/hexchat/plugins/perl/generate_header.py plugins/perl/hexchat.pm.h ../plugins/perl/lib/HexChat.pm ../plugins/perl/lib/Xchat.pm ../plugins/perl/lib/HexChat/Embed.pm ../plugins/perl/lib/HexChat/List/Network.pm ../plugins/perl/lib/HexChat/List/Network/Entry.pm ../plugins/perl/lib/HexChat/List/Network/AutoJoin.pm
/usr/bin/env: ‘python3\r’: No such file or directory
/usr/bin/env: use -[v]S to pass options in shebang lines
[3/151] Generating plugins/python/python-bindings with a custom command
FAILED: [code=127] plugins/python/python.c 
/home/neel/Projects/hexchat/plugins/python/generate_plugin.py ../plugins/python/../../src/common/hexchat-plugin.h ../plugins/python/python.py plugins/python/python.c
/usr/bin/env: ‘python3\r’: No such file or directory
/usr/bin/env: use -[v]S to pass options in shebang lines
[18/151] Compiling C object plugins/lua/lua.so.p/lua.c.o
ninja: build stopped: subcommand failed.