Improve the error message for various sequences

[PCManticore]

BPO	22077
Nosy	@terryjreedy, @PCManticore
Files	proper_error.patch

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = 'https://github.com/terryjreedy'
closed_at = <Date 2014-08-02.05:32:25.890>
created_at = <Date 2014-07-26.08:52:10.860>
labels = ['type-feature']
title = 'Improve the error message for various sequences'
updated_at = <Date 2014-08-02.05:32:25.889>
user = 'https://github.com/PCManticore'

bugs.python.org fields:

activity = <Date 2014-08-02.05:32:25.889>
actor = 'terry.reedy'
assignee = 'terry.reedy'
closed = True
closed_date = <Date 2014-08-02.05:32:25.890>
closer = 'terry.reedy'
components = []
creation = <Date 2014-07-26.08:52:10.860>
creator = 'Claudiu.Popa'
dependencies = []
files = ['36104']
hgrepos = []
issue_num = 22077
keywords = ['patch']
message_count = 3.0
messages = ['224029', '224535', '224536']
nosy_count = 3.0
nosy_names = ['terry.reedy', 'Claudiu.Popa', 'python-dev']
pr_nums = []
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue22077'
versions = ['Python 3.5']

[PCManticore]

For a couple of sequences (bytes, list, tuple, bytearray), the error when using an invalid sequence index is misleading, because it says that only integers are allowed, while slices are allowed too.

>>> a = []
>>> a['python']
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: list indices must be integers, not str
>>>

For instance, here's how range does it:

>>> range(1)['a']
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: range indices must be integers or slices, not str

The attached patch improves these error messages.

[python-dev]

New changeset 02d6d3a7a181 by Terry Jan Reedy in branch 'default':
Issue bpo-22077: Improve index error messages for bytearrays, bytes, lists, and
http://hg.python.org/cpython/rev/02d6d3a7a181

[terryjreedy]

while at it, I changed bytearray messages to include bad type as other do.