Python: json.loads chokes on escapes [duplicate]

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The correct json is:

r'{"FileExists": true, "Version": "4.3.2.1", "Path": "\\\\host\\dir\\file.exe"}'

Note the letter r if you omit it you need to escape \ for Python too.

>>> import json
>>> d = json.loads(s)
>>> d.keys()
[u'FileExists', u'Path', u'Version']
>>> d.values()
[True, u'\\\\host\\dir\\file.exe', u'4.3.2.1']

Note the difference:

>>> repr(d[u'Path'])
"u'\\\\\\\\host\\\\dir\\\\file.exe'"
>>> str(d[u'Path'])
'\\\\host\\dir\\file.exe'
>>> print d[u'Path']
\\host\dir\file.exe

Python REPL prints by default the repr(obj) for an object obj:

>>> class A:
...   __str__ = lambda self: "str"
...   __repr__  = lambda self: "repr"
... 
>>> A()
repr
>>> print A()
str

Therefore your original s string is not properly escaped for JSON. It contains unescaped '\d' and '\f'. print s must show '\\d' otherwise it is not correct JSON.

NOTE: JSON string is a collection of zero or more Unicode characters, wrapped in double quotes, using backslash escapes (json.org). I’ve skipped encoding issues (namely, transformation from byte strings to unicode and vice versa) in the above examples.

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