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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 find_third_party_modules ():
 """Find third party modules and add them to the python path."""

    parent = os.path.dirname(os.path.dirname(__file__))
    third_party = os.path.join(parent, "third_party")
    if os.path.isdir(third_party):
        sys.path.append(os.path.join(third_party, "dnspython"))