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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 startswith(self, prefix, start=None, end=None):
 """Return whether the current bitstring starts with prefix. prefix -- The bitstring to search for. start -- The bit position to start from. Defaults to 0. end -- The bit position to end at. Defaults to self.len. """

        prefix = Bits(prefix)
        start, end = self._validate_slice(start, end)
        if end < start + prefix.len:
            return False
        end = start + prefix.len
        return self._slice(start, end) == prefix