def region(self, start=<NUM_LIT:0>, end=None):
if end is None:<EOL><INDENT>end = len(self.sequence)<EOL><DEDENT>return '<STR_LIT>'.format(self.id, self.sequence[start:end])<EOL>
Returns a region of ``Sequence.sequence``, in FASTA format.

If called without kwargs, the entire sequence will be returned.

Args:

    start (int): Start position of the region to be returned. Default
        is 0.

    end (int): End position of the region to be returned. Negative values
        will function as they do when slicing strings.

Returns:

    str: A region of ``Sequence.sequence``, in FASTA format