[Tutor] replacement for constants from other languages in Python?

[Scott W]

Hey all,
I've done the usual googling, checked the Learning Python book and did 
some list searches, to no avail as of yet.

I'm _very_ used to using C style constants (preprocessor #define 
directives) or C++ const keyword style, for a variety of reasons.

I've yet to see anything covering 'how to work around the lack of 
constants in Python'...can anyone point me in the right direction here?

A few examples/reasons for use:
The 'need' to define a global constant in an imported module, for 
example- (I know about sys.version_info, but it doesn't exist in 
1.5.2...don't ask ;-)  I also know this could be handled via a class, 
but what is the equivalent of the following snippets?  Not so interested 
in style comments (I am, but not on these/this thread ;-) as much as 
other ways to do this..

1.
ourversion.py:
import sys
MINVERSION = 1.5
def checkVersion():
        """ used as an evil hack because 1.5.2 doesn't have                     
 
        sys.version_info
        """
        # Not sure why, but declaring MINVERSION as repr(foo) in the
        # first place doesn't work, something about python type handling
        # I'm sure..
        return repr(MINVERSION) >= repr(getVersion())
def getVersion():
        return sys.version[0:3]
if repr(getVersion() < 2.0)
        # boo, we have no builtin bool
        global True
        global False
        True = 1
        False = 0
funkyScopeAndConstants.py:
import ourversion.py
import sys
import os
import <someOtherModule>
...
...
if someOtherModule.property = True
        # do something
You get the point.
The other oddity is without being able to define a 'real' constant, as 
in #DEFINE MINVERSION 1.5,

the scope of MINVERSION (and True/False) even using the global keyword 
still uses the ocal file's namespace.  I don't want to debate the merits 
of using globals...most people that claim they never use any in other 
languages _still_ use constants in header files, which is the purpose 
I'd like to be able to do generally....not to mention the fact that I 
really am _not_ thrilled with the use of string literals typed in each 
time in code (yes, quick and dirty code but still) I see seems to be 
'OK' in python for the use of comparisons...opposed to something like

if(strncmp(strVal,
        CONSTANT_STRING_VAL_LIKE_HTTP_ACCEPT_ENCODING_HEADER,
        strlen(strVal)
        {
                do_something();
        }
or
if(floatVal > PI)
{
        do_something()
}
ok, hopefully that's explaining some of why I'd like a 'constant 
equivalent' as well as a question on global scoping/python namespaces.

A last question would also be if the equivalent of __FILE__ and __LINE__ 
macros exist?

Thanks,
Scott
        
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