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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 _create_trustdb(cls):
 """Create the trustdb file in our homedir, if it doesn't exist."""

    trustdb = os.path.join(cls.homedir, 'trustdb.gpg')
    if not os.path.isfile(trustdb):
        log.info("GnuPG complained that your trustdb file was missing. %s"
                 % "This is likely due to changing to a new homedir.")
        log.info("Creating trustdb.gpg file in your GnuPG homedir.")
        cls.fix_trustdb(trustdb)