'Return annotated source code for the function.'

def __str__(self):

    lines = []
    lineno = self.firstlineno
    for line in self.source:
        counter = self.sourcelines.get(lineno)
        if (counter is None):
            prefix = ('    ' * 7)
        elif (counter == 0):
            if self.blank_rx.match(line):
                prefix = ('    ' * 7)
            else:
                prefix = (('>' * 6) + '    ')
        else:
            prefix = ('%5d:    ' % counter)
        lines.append((prefix + line))
        lineno += 1
    return ''.join(lines)
