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StandAlone Parsers return different ASTs with same DSL input

See original GitHub issue

from python_parser import Lark_StandAlone

class PythonIndenter(Indenter):
    NL_type = '_NEWLINE'
    OPEN_PAREN_types = ['LPAR', 'LSQB', 'LBRACE']
    CLOSE_PAREN_types = ['RPAR', 'RSQB', 'RBRACE']
    INDENT_type = '_INDENT'
    DEDENT_type = '_DEDENT'
    tab_len = 8


simple_stmts = """
a=1
b=2

"""
kwargs = dict(postlex=PythonIndenter())

parser1 = Lark_StandAlone(**kwargs)
print(parser1.parse(simple_stmts))

parser2 = Lark_StandAlone(**kwargs)
print(parser2.parse(simple_stmts))

Two parsers are both instanced from Lark_StandAlone class and parse the same string, however, the results are two different ASTs shown as below, could you please check it for me? Thanks.

Tree(file_input, [Tree(expr_stmt, [Tree(var, [Token(NAME, 'a')]), Tree(number, [Token(DEC_NUMBER, '1')])]), Tree(expr_stmt, [Tree(var, [Token(NAME, 'b')]), Tree(number, [Token(DEC_NUMBER, '2')])])])

Tree(_cb4_NonTerminal('file_input'), [Tree(_cb448_NonTerminal('__anon_star_0'), [Tree(_cb448_NonTerminal('__anon_star_0'), [Tree(_cb447_NonTerminal('__anon_star_0'), [Token(_NEWLINE, '\n')]), Tree(_cb141_NonTerminal('stmt'), [Tree(_cb146_NonTerminal('simple_stmt'), [Tree(_cb150_NonTerminal('small_stmt'), [Tree(_cb157_NonTerminal('expr_stmt'), [Tree(_cb162_NonTerminal('testlist_star_expr'), [Tree(_cb263_NonTerminal('test'), [Tree(_cb272_NonTerminal('or_test'), [Tree(_cb274_NonTerminal('and_test'), [Tree(_cb277_NonTerminal('not_test'), [Tree(_cb278_NonTerminal('comparison'), [Tree(_cb281_NonTerminal('expr'), [Tree(_cb284_NonTerminal('xor_expr'), [Tree(_cb286_NonTerminal('and_expr'), [Tree(_cb287_NonTerminal('shift_expr'), [Tree(_cb289_NonTerminal('arith_expr'), [Tree(_cb292_NonTerminal('term'), [Tree(_cb293_NonTerminal('factor'), [Tree(_cb318_NonTerminal('power'), [Tree(_cb320_NonTerminal('await_expr'), [Tree(_cb323_NonTerminal('atom_expr'), [Tree(_cb338_NonTerminal('atom'), [Token(NAME, 'a')])])])])])])])])])])])])])])])])]), Tree(_cb463_NonTerminal('__anon_star_6'), [Token(EQUAL, '='), Tree(_cb162_NonTerminal('testlist_star_expr'), [Tree(_cb263_NonTerminal('test'), [Tree(_cb272_NonTerminal('or_test'), [Tree(_cb274_NonTerminal('and_test'), [Tree(_cb277_NonTerminal('not_test'), [Tree(_cb278_NonTerminal('comparison'), [Tree(_cb281_NonTerminal('expr'), [Tree(_cb284_NonTerminal('xor_expr'), [Tree(_cb286_NonTerminal('and_expr'), [Tree(_cb287_NonTerminal('shift_expr'), [Tree(_cb289_NonTerminal('arith_expr'), [Tree(_cb292_NonTerminal('term'), [Tree(_cb293_NonTerminal('factor'), [Tree(_cb318_NonTerminal('power'), [Tree(_cb320_NonTerminal('await_expr'), [Tree(_cb323_NonTerminal('atom_expr'), [Tree(_cb340_NonTerminal('atom'), [Tree(_cb440_NonTerminal('number'), [Token(DEC_NUMBER, '1')])])])])])])])])])])])])])])])])])])])])]), Token(_NEWLINE, '\n')])])]), Tree(_cb141_NonTerminal('stmt'), [Tree(_cb146_NonTerminal('simple_stmt'), [Tree(_cb150_NonTerminal('small_stmt'), [Tree(_cb157_NonTerminal('expr_stmt'), [Tree(_cb162_NonTerminal('testlist_star_expr'), [Tree(_cb263_NonTerminal('test'), [Tree(_cb272_NonTerminal('or_test'), [Tree(_cb274_NonTerminal('and_test'), [Tree(_cb277_NonTerminal('not_test'), [Tree(_cb278_NonTerminal('comparison'), [Tree(_cb281_NonTerminal('expr'), [Tree(_cb284_NonTerminal('xor_expr'), [Tree(_cb286_NonTerminal('and_expr'), [Tree(_cb287_NonTerminal('shift_expr'), [Tree(_cb289_NonTerminal('arith_expr'), [Tree(_cb292_NonTerminal('term'), [Tree(_cb293_NonTerminal('factor'), [Tree(_cb318_NonTerminal('power'), [Tree(_cb320_NonTerminal('await_expr'), [Tree(_cb323_NonTerminal('atom_expr'), [Tree(_cb338_NonTerminal('atom'), [Token(NAME, 'b')])])])])])])])])])])])])])])])])]), Tree(_cb463_NonTerminal('__anon_star_6'), [Token(EQUAL, '='), Tree(_cb162_NonTerminal('testlist_star_expr'), [Tree(_cb263_NonTerminal('test'), [Tree(_cb272_NonTerminal('or_test'), [Tree(_cb274_NonTerminal('and_test'), [Tree(_cb277_NonTerminal('not_test'), [Tree(_cb278_NonTerminal('comparison'), [Tree(_cb281_NonTerminal('expr'), [Tree(_cb284_NonTerminal('xor_expr'), [Tree(_cb286_NonTerminal('and_expr'), [Tree(_cb287_NonTerminal('shift_expr'), [Tree(_cb289_NonTerminal('arith_expr'), [Tree(_cb292_NonTerminal('term'), [Tree(_cb293_NonTerminal('factor'), [Tree(_cb318_NonTerminal('power'), [Tree(_cb320_NonTerminal('await_expr'), [Tree(_cb323_NonTerminal('atom_expr'), [Tree(_cb340_NonTerminal('atom'), [Tree(_cb440_NonTerminal('number'), [Token(DEC_NUMBER, '2')])])])])])])])])])])])])])])])])])])])])]), Token(_NEWLINE, '\n\n')])])])])