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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 read_entry(self, entry):
 """ Read the contents of an entry in this container, and return them as a byte string. Return ``None`` if the entry is not safe or it cannot be found. :rtype: byte string :raises: same as :func:`~aeneas.container.Container.entries` """

        if not self.is_entry_safe(entry):
            self.log([u"Accessing entry '%s' is not safe", entry])
            return None

        if entry not in self.entries:
            self.log([u"Entry '%s' not found in this container", entry])
            return None

        self.log([u"Reading contents of entry '%s'", entry])
        try:
            return self.actual_container.read_entry(entry)
        except:
            self.log([u"An error occurred while reading the contents of '%s'", entry])
            return None