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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def open(self, name, mode='r', *args, **kwargs):
        ''' Find a resource and return a file object, or raise IOError. '''
        fname = self.lookup(name)
        if not fname: raise IOError("Resource %r not found." % name)
        return self.opener(fname, mode=mode, *args, **kwargs)