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This bug concerns the pdeps script, <python directory>\Tools\Scripts\pdeps.py. This script opens a list of files and extracts a list of their inter-dependencies.
I'm running Python 3.1.1 on Windows XP, installed via binary installer, but have confirmed that the bug is present in the source distribution of Python 3.2 rc2, the newest code I know of. (In fact, the only difference between the pdeps.py files in each version was the shebang line, 3.2 rc2 shebang line: "#! /usr/bin/env python3", 3.1.1 shebang line: "#! /usr/bin/env python".)
When I tried out the module I found a series of small bugs, basically typos, each of which caused the script to crash due to an unhandled exception.
1.
The relevant section of the unmodified pdeps.py file
----
# Compiled regular expressions to search for import statements
#
m_import = re.compile('^[ \t]*from[ \t]+([^ \t]+)[ \t]+')
m_from = re.compile('^[ \t]*import[ \t]+([^#]+)')
# Collect data from one file
#
def process(filename, table):
...
 if m_import.match(line) >= 0:
 (a, b), (a1, b1) = m_import.regs[:2]
 elif m_from.match(line) >= 0:
 (a, b), (a1, b1) = m_from.regs[:2]
...
The match method of a compiled regular expression returns an SREMatch object, so the conditionals must be changed. In addition, the regs data is a member of the match object itself, not the compiled expression object, so the right side of the assignments must also be changed.
modified version
----
...
 import_match = m_import.match(line)
 from_match = m_from.match(line)
 if import_match:
 (a, b), (a1, b1) = import_match.regs[:2]
 elif from_match:
 (a, b), (a1, b1) = from_match.regs[:2]
...
2.
unmodified
----
# Invert a table (this is again totally general).
# All keys of the original table are made keys of the inverse,
# so there may be empty lists in the inverse.
#
def inverse(table):
 inv = {}
 for key in table.keys():
 if not inv.has_key(key):
 inv[key] = []
 for item in table[key]:
 store(inv, item, key)
 return inv
Dictionaries have no has_key method, though I vaguely recall that they used to. That's a quick fix though.
modified
----
# Invert a table (this is again totally general).
# All keys of the original table are made keys of the inverse,
# so there may be empty lists in the inverse.
#
def inverse(table):
 inv = {}
 for key in table.keys():
 if key in inv:
 inv[key] = []
 for item in table[key]:
 store(inv, item, key)
 return inv
output of fc, windows file comparing utility, run on the pdeps file from 3.2 rc2, and the modified pdeps file from 3.1.1
----
>fc original-pdeps.py pdeps.py
Comparing files original-pdeps.py and PDEPS.PY
***** original-pdeps.py 
#! /usr/bin/env python3
***** PDEPS.PY
#! /usr/bin/env python
*****
***** original-pdeps.py 
 line = line[:-1] + nextline
 if m_import.match(line) >= 0:
 (a, b), (a1, b1) = m_import.regs[:2]
 elif m_from.match(line) >= 0:
 (a, b), (a1, b1) = m_from.regs[:2]
 else: continue
***** PDEPS.PY
 line = line[:-1] + nextline
 import_match = m_import.match(line)
 from_match = m_from.match(line)
 if import_match:
 (a, b), (a1, b1) = import_match.regs[:2]
 elif from_match:
 (a, b), (a1, b1) = from_match.regs[:2]
 else: continue
*****
***** original-pdeps.py 
 for key in table.keys():
 if not inv.has_key(key):
 inv[key] = []
***** PDEPS.PY
 for key in table.keys():
 if key in inv:
 inv[key] = []
*****
With these changes the pdep script works as expected.
This is a pretty lower priority bug imho. It prevents anyone from using the script, but fixing the bug took about 5 minutes, and I doubt the pdeps script gets much use anyway. This bug is unlikely to inconvenience anyone.