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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 _compile(cls, lines):
        '''Return macro or block name from the current line.'''
        m = cls.RE_PASTE.match(lines.current)
        if m is None:
            raise MacroBlockUsageError(
                'Incorrect macro or block usage at line {}, {}\nShould be '
                'something like: #my_macro'.format(lines.pos, lines.current))
        return m.group(1)