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ericvsmithericvsmith
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Implementation of PEP 3101, Advanced String Formatting.
Known issues: The string.Formatter class, as discussed in the PEP, is incomplete. Error handling needs to conform to the PEP. Need to fix this warning that I introduced in Python/formatter_unicode.c: Objects/stringlib/unicodedefs.h:26: warning: `STRINGLIB_CMP' defined but not used Need to make sure sign formatting is correct, more tests needed. Need to remove '()' sign formatting, left over from an earlier version of the PEP.
1 parent e4dc324 commit 8c66326

22 files changed

+2669
-18
lines changed

‎Include/formatter_unicode.h‎

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PyObject *
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unicode_unicode__format__(PyObject *self, PyObject *args);
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PyObject *
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unicode_long__format__(PyObject *self, PyObject *args);
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PyObject *
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unicode_float__format__(PyObject *self, PyObject *args);
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‎Include/unicodeobject.h‎

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@@ -1437,6 +1437,11 @@ PyAPI_FUNC(Py_UNICODE*) Py_UNICODE_strchr(
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const Py_UNICODE *s, Py_UNICODE c
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);
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PyObject *
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_unicodeformatter_iterator(PyObject *str);
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PyObject *
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_unicodeformatter_lookup(PyObject *field_name, PyObject *args,
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PyObject *kwargs);
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#ifdef __cplusplus
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}

‎Lib/string.py‎

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@@ -189,3 +189,42 @@ def convert(mo):
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raise ValueError('Unrecognized named group in pattern',
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self.pattern)
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return self.pattern.sub(convert, self.template)
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########################################################################
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# the Formatter class
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# see PEP 3101 for details and purpose of this class
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# The hard parts are reused from the C implementation. They're
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# exposed here via the sys module. sys was chosen because it's always
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# available and doesn't have to be dynamically loaded.
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# The parser is implemented in sys._formatter_parser.
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# The "object lookup" is implemented in sys._formatter_lookup
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from sys import _formatter_parser, _formatter_lookup
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class Formatter:
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def format(self, format_string, *args, **kwargs):
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return self.vformat(format_string, args, kwargs)
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def vformat(self, format_string, args, kwargs):
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result = []
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for (is_markup, literal, field_name, format_spec, conversion) in \
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_formatter_parser(format_string):
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if is_markup:
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# find the object
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index, name, obj = _formatter_lookup(field_name, args, kwargs)
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else:
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result.append(literal)
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return ''.join(result)
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def get_value(self, key, args, kwargs):
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pass
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def check_unused_args(self, used_args, args, kwargs):
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pass
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def format_field(self, value, format_spec):
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pass

‎Lib/test/test_builtin.py‎

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@@ -517,6 +517,32 @@ def __float__(self):
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self.assertAlmostEqual(float(Foo3(21)), 42.)
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self.assertRaises(TypeError, float, Foo4(42))
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def test_format(self):
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class A:
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def __init__(self, x):
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self.x = x
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def __format__(self, format_spec):
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return str(self.x) + format_spec
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# class that returns a bad type from __format__
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class H:
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def __format__(self, format_spec):
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return 1.0
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self.assertEqual(format(3, ''), '3')
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self.assertEqual(format(A(3), 'spec'), '3spec')
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# for builtin types, format(x, "") == str(x)
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self.assertEqual(format(17**13, ""), str(17**13))
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self.assertEqual(format(1.0, ""), str(1.0))
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self.assertEqual(format(3.1415e104, ""), str(3.1415e104))
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self.assertEqual(format(-3.1415e104, ""), str(-3.1415e104))
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self.assertEqual(format(3.1415e-104, ""), str(3.1415e-104))
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self.assertEqual(format(-3.1415e-104, ""), str(-3.1415e-104))
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self.assertEqual(format(object, ""), str(object))
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#self.assertRaises(TypeError, format, H(), "")
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def test_getattr(self):
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import sys
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self.assert_(getattr(sys, 'stdout') is sys.stdout)

‎Lib/test/test_descrtut.py‎

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'__delslice__',
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'__doc__',
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'__eq__',
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'__format__',
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'__ge__',
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'__getattribute__',
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'__getitem__',

‎Lib/test/test_float.py‎

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@@ -114,12 +114,44 @@ def neg_neg():
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self.assertEquals(pos_pos(), neg_pos())
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self.assertEquals(pos_neg(), neg_neg())
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class FormatTestCase(unittest.TestCase):
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def testFormat(self):
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# these should be rewritten to use both format(x, spec) and
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# x.__format__(spec)
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self.assertEqual(format(0.0, 'f'), '0.000000')
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# the default is 'g', except for empty format spec
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self.assertEqual(format(0.0, ''), '0.0')
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self.assertEqual(format(0.01, ''), '0.01')
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self.assertEqual(format(0.01, 'g'), '0.01')
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self.assertEqual(format(0, 'f'), '0.000000')
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self.assertEqual(format(1.0, 'f'), '1.000000')
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self.assertEqual(format(1, 'f'), '1.000000')
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self.assertEqual(format(-1.0, 'f'), '-1.000000')
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self.assertEqual(format(-1, 'f'), '-1.000000')
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self.assertEqual(format( 1.0, ' f'), ' 1.000000')
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self.assertEqual(format(-1.0, ' f'), '-1.000000')
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self.assertEqual(format( 1.0, '+f'), '+1.000000')
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self.assertEqual(format(-1.0, '+f'), '-1.000000')
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# % formatting
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self.assertEqual(format(-1.0, '%'), '-100.000000%')
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# conversion to string should fail
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self.assertRaises(ValueError, format, 3.0, "s")
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def test_main():
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test_support.run_unittest(
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FormatFunctionsTestCase,
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UnknownFormatTestCase,
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IEEEFormatTestCase)
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IEEEFormatTestCase,
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FormatTestCase)
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if __name__ == '__main__':
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test_main()

‎Lib/test/test_long.py‎

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@@ -493,6 +493,50 @@ def __cmp__(self, other):
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eq(x > y, Rcmp > 0, Frm("%r > %r %d", x, y, Rcmp))
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eq(x >= y, Rcmp >= 0, Frm("%r >= %r %d", x, y, Rcmp))
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def test_format(self):
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self.assertEqual(format(123456789, 'd'), '123456789')
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self.assertEqual(format(123456789, 'd'), '123456789')
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# hex
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self.assertEqual(format(3, "x"), "3")
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self.assertEqual(format(3, "X"), "3")
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self.assertEqual(format(1234, "x"), "4d2")
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self.assertEqual(format(-1234, "x"), "-4d2")
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self.assertEqual(format(1234, "8x"), " 4d2")
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# XXX fix self.assertEqual(format(-1234, "8x"), " -4d2")
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self.assertEqual(format(1234, "x"), "4d2")
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self.assertEqual(format(-1234, "x"), "-4d2")
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self.assertEqual(format(-3, "x"), "-3")
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self.assertEqual(format(-3, "X"), "-3")
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self.assertEqual(format(int('be', 16), "x"), "be")
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self.assertEqual(format(int('be', 16), "X"), "BE")
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self.assertEqual(format(-int('be', 16), "x"), "-be")
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self.assertEqual(format(-int('be', 16), "X"), "-BE")
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# octal
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self.assertEqual(format(3, "b"), "11")
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self.assertEqual(format(-3, "b"), "-11")
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self.assertEqual(format(1234, "b"), "10011010010")
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self.assertEqual(format(-1234, "b"), "-10011010010")
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self.assertEqual(format(1234, "-b"), "10011010010")
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self.assertEqual(format(-1234, "-b"), "-10011010010")
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self.assertEqual(format(1234, " b"), " 10011010010")
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self.assertEqual(format(-1234, " b"), "-10011010010")
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self.assertEqual(format(1234, "+b"), "+10011010010")
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self.assertEqual(format(-1234, "+b"), "-10011010010")
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# conversion to float
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self.assertEqual(format(0, 'f'), '0.000000')
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# make sure these are errors
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self.assertRaises(ValueError, format, 3, "1.3") # precision disallowed
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return
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self.assertRaises(ValueError, format, 3, "+c") # sign not allowed
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# with 'c'
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self.assertRaises(ValueError, format, 3, "R") # bogus format type
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# conversion to string should fail
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self.assertRaises(ValueError, format, 3, "s")
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def test_main():
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test_support.run_unittest(LongTest)
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‎Lib/test/test_string.py‎

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@@ -15,6 +15,14 @@ def test_attrs(self):
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string.punctuation
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string.printable
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def test_formatter(self):
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fmt = string.Formatter()
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self.assertEqual(fmt.format("foo"), "foo")
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# Formatter not working you for lookups
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#self.assertEqual(fmt.format("foo{0}", "bar"), "foobar")
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def test_maketrans(self):
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transtable = '\000\001\002\003\004\005\006\007\010\011\012\013\014\015\016\017\020\021\022\023\024\025\026\027\030\031\032\033\034\035\036\037 !"#$%&\'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`xyzdefghijklmnopqrstuvwxyz{|}~\177\200\201\202\203\204\205\206\207\210\211\212\213\214\215\216\217\220\221\222\223\224\225\226\227\230\231\232\233\234\235\236\237\240\241\242\243\244\245\246\247\250\251\252\253\254\255\256\257\260\261\262\263\264\265\266\267\270\271\272\273\274\275\276\277\300\301\302\303\304\305\306\307\310\311\312\313\314\315\316\317\320\321\322\323\324\325\326\327\330\331\332\333\334\335\336\337\340\341\342\343\344\345\346\347\350\351\352\353\354\355\356\357\360\361\362\363\364\365\366\367\370\371\372\373\374\375\376\377'
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