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""" 
This disables builtin functions (and one exception class) which are 
removed from Python 3.3. 
 
This module is designed to be used like this:: 
 
    from future.builtins.disabled import * 
 
This disables the following obsolete Py2 builtin functions:: 
 
    apply, cmp, coerce, execfile, file, input, long, 
    raw_input, reduce, reload, unicode, xrange 
 
We don't hack __builtin__, which is very fragile because it contaminates 
imported modules too. Instead, we just create new functions with 
the same names as the obsolete builtins from Python 2 which raise 
NameError exceptions when called. 
 
Note that both ``input()`` and ``raw_input()`` are among the disabled 
functions (in this module). Although ``input()`` exists as a builtin in 
Python 3, the Python 2 ``input()`` builtin is unsafe to use because it 
can lead to shell injection. Therefore we shadow it by default upon ``from 
future.builtins.disabled import *``, in case someone forgets to import our 
replacement ``input()`` somehow and expects Python 3 semantics. 
 
See the ``future.builtins.misc`` module for a working version of 
``input`` with Python 3 semantics. 
 
(Note that callable() is not among the functions disabled; this was 
reintroduced into Python 3.2.) 
 
This exception class is also disabled: 
 
    StandardError 
 
""" 
 
from __future__ import division, absolute_import, print_function 
 
from future import utils 
 
 
OBSOLETE_BUILTINS = ['apply', 'chr', 'cmp', 'coerce', 'execfile', 'file', 
                     'input', 'long', 'raw_input', 'reduce', 'reload', 
                     'unicode', 'xrange', 'StandardError'] 
 
 
def disabled_function(name): 
    ''' 
    Returns a function that cannot be called 
    ''' 
    def disabled(*args, **kwargs): 
        ''' 
        A function disabled by the ``future`` module. This function is 
        no longer a builtin in Python 3. 
        ''' 
        raise NameError('obsolete Python 2 builtin {0} is disabled'.format(name)) 
    return disabled 
 
 
if not utils.PY3: 
    for fname in OBSOLETE_BUILTINS: 
        locals()[fname] = disabled_function(fname) 
    __all__ = OBSOLETE_BUILTINS 
else: 
    __all__ = []