.TH python pj "4 July 2005"
.SH NAME
Python Notes
.SH DESCRIPTION
Python loads modules using a PATH-like variable called PYTHONPATH. From within python, you can get this as sys.path.
.PP
If Python finds a module package in sys.path, it looks there for all submodules, and does not check the rest of sys.path. For instance, say you have this on your filesystem:
.PP
.RS
.nf
/a/pythonlib/MyPackage/MyModuleA
/b/pythonlib/MyPackage/MyModuleA
/b/pythonlib/MyPackage/MyModuleB
.fi
.RE
.PP
And say this is your sys.path: ['/a/pythonlib', '/b/pythonlib']. Then you will never find MyPackage.MyModuleB, because when Python sees MyPackage in /a/pythonlib, it will always look there for submodules.
.PP
If you're trying to figure out how to print stack traces, use the traceback module. Just call print_exc() if you're in an except handler, or print_stack() if you're not. There are other functions that operate on specific exception/traceback objects; see the documentation. And the exc_info() function isn't documented very well. It doesn't return a traceback object; it returns a tuple the third member of which is a traceback object.
.PP
If you want to format an exception for printing, you can do something along these lines:
.PP
.RS
.nf
try:
    a = b
except:
    import traceback, sys
    print traceback.format_tb(sys.exc_info()[2])[0]
.fi
.RE
.SH AUTHOR
Paul Jungwirth
.SH COPYRIGHT
Copyright \(co 2005 Paul Jungwirth