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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 srp1(*args, **kargs):
 """Send and receive packets at layer 2 and return only the first answer"""

    ans, _ = srp(*args, **kargs)
    if len(ans) > 0:
        return ans[0][1]
    else:
        return None