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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 trim(self, begin=None, length=None):
 """ Get a slice of the audio data of ``length`` seconds, starting from ``begin`` seconds. If audio data is not loaded, load it and then slice it. :param begin: the start position, in seconds :type begin: :class:`~aeneas.exacttiming.TimeValue` :param length: the position, in seconds :type length: :class:`~aeneas.exacttiming.TimeValue` :raises: TypeError: if one of the arguments is not ``None`` or :class:`~aeneas.exacttiming.TimeValue` .. versionadded:: 1.2.0 """

        for variable, name in [(begin, "begin"), (length, "length")]:
            if (variable is not None) and (not isinstance(variable, TimeValue)):
                raise TypeError(u"%s is not None or TimeValue" % name)
        self.log(u"Trimming...")
        if (begin is None) and (length is None):
            self.log(u"begin and length are both None: nothing to do")
        else:
            if begin is None:
                begin = TimeValue("0.000")
                self.log([u"begin was None, now set to %.3f", begin])
            begin = min(max(TimeValue("0.000"), begin), self.audio_length)
            self.log([u"begin is %.3f", begin])
            if length is None:
                length = self.audio_length - begin
                self.log([u"length was None, now set to %.3f", length])
            length = min(max(TimeValue("0.000"), length), self.audio_length - begin)
            self.log([u"length is %.3f", length])
            begin_index = int(begin * self.audio_sample_rate)
            end_index = int((begin + length) * self.audio_sample_rate)
            new_idx = end_index - begin_index
            self.__samples[0:new_idx] = self.__samples[begin_index:end_index]
            self.__samples_length = new_idx
            self._update_length()
        self.log(u"Trimming... done")