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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 str_repr(klass):
 """ Implements string conversion methods for the given class. The given class must implement the __str__ method. This decorat will add __repr__ and __unicode__ (for Python 2). """

    if PY2:
        klass.__unicode__ = klass.__str__
        klass.__str__ = lambda self: self.__unicode__().encode('utf-8')
    klass.__repr__ = lambda self: '<%s: %r>' % (self.__class__.__name__, str(self))
    return klass