<Tr> <Th_colspan="2"> Series </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="3"> Originally aired </Th> </Tr> <Tr> <Th> First aired </Th> <Th> Last aired </Th> <Th> Network </Th> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> </Td> <Td_colspan="1"> 4 December 2011 (2011 - 12 - 04) </Td> <Td> 18 December 2011 (2011 - 12 - 18) </Td> <Td> Channel 4 </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> </Td> <Td_colspan="1"> 11 February 2013 (2013 - 02 - 11) </Td> <Td> 25 February 2013 (2013 - 02 - 25) </Td> </Tr>

How many episodes are in season one of black mirror
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