when you install weewx using setup.py and the default home location of /home/weewx, the weewx 'bin' directory is
/home/weewx/bin
when you install weewx using the debian or redhat or suse packages, the bin directory is
/usr/share/weewx
the bin directory and other file locations are documented in the weewx user guide
http://weewx.com/docs/usersguide.htm#installing
specifically in the table in section 4.2
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