@property<EOL><INDENT>def accession(self):<DEDENT>
accession = None<EOL>if self.defline.startswith('<STR_LIT>'):<EOL><INDENT>match = re.match('<STR_LIT>', self.defline)<EOL>if match:<EOL><INDENT>accession = match.group(<NUM_LIT:1>)<EOL><DEDENT><DEDENT>elif self.defline.startswith('<STR_LIT>'):<EOL><INDENT>match = re.match('<STR_LIT>', self.defline)<EOL>if match:<EOL><INDENT>accession = match.group(<NUM_LIT:1>)<EOL><DEDENT><DEDENT>elif self.defline.startswith('<STR_LIT>'):<EOL><INDENT>match = re.match('<STR_LIT>', self.defline)<EOL>if match:<EOL><INDENT>accession = match.group(<NUM_LIT:1>)<EOL><DEDENT><DEDENT>return accession<EOL>
Parse accession number from commonly supported formats.

If the defline does not match one of the following formats, the entire
description (sans leading caret) will be returned.

* >gi|572257426|ref|XP_006607122.1|
* >gnl|Tcas|XP_008191512.1
* >lcl|PdomMRNAr1.2-10981.1