'Writes a common header for the generated files.'

def _get_header(self):

    code_lines = []
    code_lines.append((('!' + ('*' * 78)) + '\n'))
    tmp = (header_comment % {'version': sympy_version, 'project': self.project})
    for line in tmp.splitlines():
        code_lines.append(('!*%s*\n' % line.center(76)))
    code_lines.append((('!' + ('*' * 78)) + '\n'))
    return code_lines
