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diff --git a/decorator.py b/decorator.py
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+##########################     LICENCE    ###############################
+      
+##   Redistributions of source code must retain the above copyright 
+##   notice, this list of conditions and the following disclaimer.
+##   Redistributions in bytecode form must reproduce the above copyright
+##   notice, this list of conditions and the following disclaimer in
+##   the documentation and/or other materials provided with the
+##   distribution. 
+
+##   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+##   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+##   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+##   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+##   HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+##   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+##   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+##   OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+##   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+##   TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+##   USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+##   DAMAGE.
+
+"""
+Decorator module, see http://pypi.python.org/pypi/decorator
+for the documentation.
+"""
+
+## The basic trick is to generate the source code for the decorated function
+## with the right signature and to evaluate it.
+
+__all__ = ["decorator", "makefn", "getsignature", "upgrade_dec"]
+
+import os, sys, re, inspect, warnings
+from tempfile import mkstemp
+
+DEF = re.compile('\s*def\s*([_\w][_\w\d]*)\s*\(')
+
+def _callermodule(level=2):
+    return sys._getframe(level).f_globals.get('__name__', '?')
+ 
+def getsignature(func):
+    "Return the signature of a function as a string"
+    argspec = inspect.getargspec(func)
+    return inspect.formatargspec(formatvalue=lambda val: "", *argspec)[1:-1]
+
+class FuncData(object):
+    def __init__(self, func=None, name=None, signature=None,
+                 defaults=None, doc=None, module=None, funcdict=None):
+        if func: # func can also be a class or a callable
+            self.name = func.__name__
+            self.doc = func.__doc__
+            self.module = func.__module__
+            if inspect.isfunction(func):
+                self.signature = getsignature(func)
+                self.defaults = func.func_defaults
+                self.dict = func.__dict__
+        if name:
+            self.name = name
+        if signature:
+            self.signature = signature
+        if defaults:
+            self.defaults = defaults
+        if doc:
+            self.doc = doc
+        if module:
+            self.module = module
+        if funcdict:
+            self.dict = funcdict
+
+    def update(self, func, **kw):
+        func.__name__ = getattr(self, 'name', 'noname')
+        func.__doc__ = getattr(self, 'doc', None)
+        func.__dict__ = getattr(self, 'dict', {})
+        func.func_defaults = getattr(self, 'defaults', None)
+        func.__module__ = getattr(self, 'module', _callermodule())
+        func.__dict__.update(kw)
+        return func
+    
+    def __getitem__(self, name):
+        return getattr(self, name)
+    
+def makefn(src, funcdata, save_source=True, **evaldict):
+    src += os.linesep # add a newline just for safety
+    name = DEF.match(src).group(1) # extract the function name from the source
+    if save_source:
+        fhandle, fname = mkstemp()
+        os.write(fhandle, src)
+        os.close(fhandle)
+    else:
+        fname = '?'
+    code = compile(src, fname, 'single')
+    exec code in evaldict
+    func = evaldict[name]
+    return funcdata.update(func, __source__=src)
+
+def decorator(caller, func=None):
+    """
+    decorator(caller) converts a caller function into a decorator;
+    decorator(caller, func) is akin to decorator(caller)(func).
+    """
+    if func:
+        fd = FuncData(func)
+        name = fd.name
+        signature = fd.signature
+        for arg in signature.split(','):
+            argname = arg.strip(' *')
+            assert not argname in('_func_', '_call_'), (
+               '%s is a reserved argument name!' % argname)
+        src = """def %(name)s(%(signature)s):
+        return _call_(_func_, %(signature)s)""" % locals()
+        return makefn(src, fd, save_source=False, _func_=func, _call_=caller)
+    src = 'def %s(func): return decorator(caller, func)' % caller.__name__
+    return makefn(src, FuncData(caller), save_source=False,
+                  caller=caller, decorator=decorator)
+
+@decorator
+def deprecated(func, *args, **kw):
+    "A decorator for deprecated functions"
+    warnings.warn('Calling the deprecated function %r' % func.__name__,
+                  DeprecationWarning, stacklevel=3)
+    return func(*args, **kw)
+
+def upgrade_dec(dec):
+    def new_dec(func):
+        fd = FuncData(func)
+        src = '''def %(name)s(%(signature)s):
+        return decorated(%(signature)s)''' % fd
+        return makefn(src, fd, save_source=False, decorated=dec(func))
+    return FuncData(dec).update(new_dec)