def get_column(self, position, missing_seqs=MissingSequenceHandler.SKIP):
res = {}<EOL>for k in self.sequences:<EOL><INDENT>if isinstance(self.sequences[k], UnknownSequence):<EOL><INDENT>if missing_seqs is MissingSequenceHandler.TREAT_AS_ALL_GAPS:<EOL><INDENT>res[k] = "<STR_LIT:->"<EOL><DEDENT>elif missing_seqs is MissingSequenceHandler.SKIP:<EOL><INDENT>continue<EOL><DEDENT><DEDENT>else:<EOL><INDENT>res[k] = self.sequences[k][position - <NUM_LIT:1>]<EOL><DEDENT><DEDENT>return res<EOL>
return a column from an alignment as a dictionary indexed by seq. name.

:param position:     the index to extract; these are in alignment
                     co-ordinates, which are one-based, so the first column
                     has index 1, and the final column has
                     index == size(self).
:param missing_seqs: how to treat sequence with no actual sequence data for
                     the column.
:return: dictionary where keys are sequence names and values are
         nucleotides (raw strings).