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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 wraplet_signature(app, what, name, obj, options, signature, return_annotation):
 """have wrapplets use the signature of the slave"""

    try:
        wrapped = obj._raw_slave
    except AttributeError:
        return None
    else:
        slave_argspec = autodoc.getargspec(wrapped)
        slave_signature = autodoc.formatargspec(obj, *slave_argspec)
        return (slave_signature, return_annotation)