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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def sync_sources(self, force=False):
 """Sync in only the sources.csv file"""

        from ambry.orm.file import File

        self.dstate = self.STATES.BUILDING

        synced = 0

        for fc in [File.BSFILE.SOURCES]:
            bsf = self.build_source_files.file(fc)
            if bsf.fs_is_newer or force:
                self.log('Syncing {}'.format(bsf.file_name))
                bsf.fs_to_objects()
                synced += 1

        return synced