Question

I have a lookup table hard-coded in python at the moment that looks something like:

   lookup = {
       "\x85": u'...', # ...
       "\x91": u"'",
       ...
   }

I would like to move the mapping to an external file to make it easier to manage, but have not been able to find a way to store x-escaped character codes and read them back in. Instead of ‘\x85’, I end up with ‘\x85’.

Any ideas?

Answer 1

If you format the file like so:

{
       "\x85": u'...',
       "\x91": u"'"
}

Then you can use ast.literal_eval() to get the lookup table into your program:

In [10]: ast.literal_eval(open('lookup.txt').read())
Out[10]: {'\x85': u'...', '\x91': u"'"}

If you want to employ a custom format, you could just store the hex ASCII codes for the keys (e.g. 85, 91 etc), and convert them while reading:

In [17]: chr(int('91', 16))
Out[17]: '\x91'