# -*- coding: utf-8 -*-
from Bio._py3k import basestring
[docs]def _prepare_sequence(seq_record):
"""Outputs a DNA sequence as string.
:param seq_record: Either sequence as string or sequence object
:return: sequence as string
"""
if isinstance(seq_record, basestring):
return seq_record
else:
try:
return str(seq_record.seq)
except AttributeError:
raise AttributeError("No valid sequence was found for %s." % seq_record)