Sequence item 0 expected str instance list found ошибка

I’m trying to print all of the possible character substitutions for the word «otaku».

#!/usr/bin/python3

import itertools

user_input = "otaku"

dict = {
'c': ['c', 'C'],
'a': ['a', 'A', '@'],
't': ['t', 'T'],
'k': ['k', 'K'],
'u': ['u', 'U'],
'e': ['e', 'E', '3'],
'o': ['o', 'O', '0']
}

output = ""

for i in itertools.product(dict['o'],dict['t'],dict['a'],dict['k'],dict['u']):
    output += ''.join(i) + "n"

print(output)

The above script works but I need the itertools.product() input (dict['o'],dict['t'],dict['a'],dict['k'],dict['u']) to be dynamic (e.g., new_list):

#!/usr/bin/python3

import itertools

user_input = "otaku"

dict = {
'c': ['c', 'C'],
'a': ['a', 'A', '@'],
't': ['t', 'T'],
'k': ['k', 'K'],
'u': ['u', 'U'],
'e': ['e', 'E', '3'],
'o': ['o', 'O', '0']
}

new_list = []

for i in user_input:
    new_list.append(dict[i])

output = ""

for i in itertools.product(new_list):
    output += ''.join(i) + "n"

print(output)

This errors with:

TypeError: sequence item 0: expected str instance, list found

I tried the solutions found here, but converting the list to a str breaks the itertools.product line.

How can I pass dynamic input into itertools.product()?

Desired output:

otaku
otakU
otaKu
otaKU
otAku
otAkU
otAKu
otAKU
ot@ku
ot@kU
ot@Ku
ot@KU
oTaku
oTakU
oTaKu
oTaKU
oTAku
oTAkU
oTAKu
oTAKU
oT@ku
oT@kU
oT@Ku
oT@KU
Otaku
OtakU
OtaKu
OtaKU
Ot@KU

The error “TypeError: sequence item 0: expected str instance, int found” happens when you try to join some numbers of type ‘int’ into a new string. The explanation of this guide will help you fix this error and other similar errors you may get in your code. 

In Python, join() method joins all items in a collection as a list, a tuple,… to a string. Here is an example using the join() method to join all the strings in a list to a new string with commas separate.

device_list = ["smartphone", "tablet", "laptop", "desktop"]
device_str = ','.join(device_list)
print(device_str)

Output:

smartphone,tablet,laptop,desktop

Sometimes, you may want to join a list of integer numbers to a string, and you try to do the same as the example above, but your code does not work as you expected, and you get the error “TypeError: sequence item 0: expected str instance, int found”. 

year_list = [2022, 2023, 2024, 2025]
year_str = ','.join(year_list)
print(year_str)

Output:

    year_str = ','.join(year_list)
TypeError: sequence item 0: expected str instance, int found

How to solve the error?

Method 1: Use Python List Comprehension to create a new list of strings

This error occurs because the join() method requires the list has all of its elements of type ‘str’, not ‘int’. So, to fix this error, you can use the List Comprehension of Python to create a list of strings from the original list as this example.

year_list = [2022, 2023, 2024, 2025]
year_str = ','.join([str(year) for year in year_list])
print(year_str)

Output:

2022,2023,2024,2025

Method 2: Use map() function

Another way to fix this error is to use the map() function, which applies a function to all elements of the list. In this case, the function you need to use with the map() function is the str() function to convert the element to a string.

year_list = [2022, 2023, 2024, 2025]
year_str = ','.join(map(str, year_list))
print(year_str)

Output:

2022,2023,2024,2025

Example with a list of multiple datatypes

Both solutions above work not only with a list of integer numbers but also with a list of multiple datatypes.

exam_scores = [8, 8.25, "9.5"]
str1 = ','.join([str(s) for s in exam_scores])
str2 = ','.join(map(str, exam_scores))
print('str1: ' + str1)
print('str2: ' + str2)

Output:

str1: 8,8.25,9.5
str2: 8,8.25,9.5

As you can see, the results of both str1 and str2 are the same and work perfectly.

Summary

In this guide, I’ve showed you how to solve the error “TypeError: sequence item 0: expected str instance, int found” in Python. You can choose to use List Comprehension to create a new list of strings or use the map() function to solve the problem. Both solutions can also work perfectly with a list of multiple datatypes.

Maybe you are interested:

• TypeError: slice indices must be integers or None or have an __index__ method
• typeerror: string indices must be integers in python
• typeerror: takes 1 positional argument but 2 were given
• TypeError: unhashable type: ‘dict’

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Hi,
I have the same problem.

You can see my debug
[Phpcs] php -l -d display_errors=On /Users/julien/Sites/www/project/application/frontend/controllers/access.php
[Phpcs] php -l -d display_errors=On /Users/julien/Sites/www/project/application/frontend/controllers/access.php
[Phpcs] cwd: /Users/julien
[Phpcs] No syntax errors detected in /Users/julien/Sites/www/project/application/frontend/controllers/access.php

[Phpcs] phpcs —report=checkstyle —standard=PSR2 -n /Users/julien/Sites/www/project/application/frontend/controllers/access.php
[Phpcs] phpcs —report=checkstyle —standard=PSR2 -n /Users/julien/Sites/www/project/application/frontend/controllers/access.php
[Phpcs] cwd: /Users/julien
Traceback (most recent call last):
File «/Applications/Sublime Text.app/Contents/MacOS/sublime_plugin.py», line 556, in run_
return self.run(edit)
File «phpcs in /Users/julien/Library/Application Support/Sublime Text 3/Installed Packages/Phpcs.sublime-package», line 649, in run
File «phpcs in /Users/julien/Library/Application Support/Sublime Text 3/Installed Packages/Phpcs.sublime-package», line 467, in run
File «phpcs in /Users/julien/Library/Application Support/Sublime Text 3/Installed Packages/Phpcs.sublime-package», line 143, in get_errors
File «phpcs in /Users/julien/Library/Application Support/Sublime Text 3/Installed Packages/Phpcs.sublime-package», line 219, in execute
File «phpcs in /Users/julien/Library/Application Support/Sublime Text 3/Installed Packages/Phpcs.sublime-package», line 222, in parse_report
File «phpcs in /Users/julien/Library/Application Support/Sublime Text 3/Installed Packages/Phpcs.sublime-package», line 173, in shell_out
File «./subprocess.py», line 824, in init
File «./subprocess.py», line 1448, in _execute_child
FileNotFoundError: [Errno 2] No such file or directory: ‘phpcs’

When I execute the command (phpcs —report=checkstyle —standard=PSR2 -n /Users/julien/Sites/www/project/application/frontend/controllers/access.php) in a terminal, I have no problem and I get the error list.

My sublime config file

{
«auto_complete»: true,
«bold_folder_labels»: true,
«color_scheme»: «Packages/Color Scheme — Default/Monokai Bright.tmTheme»,
«draw_minimap_border»: false,
«extensions_to_blacklist»:
[
],
«extensions_to_execute»:
[
«php»,
«inc»
],
«find_selected_text»: false,
«font_size»: 16,
«gutter»: true,
«highlight_line»: true,
«ignored_packages»:
[
«Vintage»
],
«line_padding_bottom»: 1,
«match_brackets»: true,
«match_brackets_angle»: false,
«match_brackets_braces»: true,
«match_brackets_content»: true,
«match_brackets_square»: true,
«php_cs_fixer_additional_args»:
{
},
«php_cs_fixer_executable_path»: «/usr/local/php5/bin/php-cs-fixer»,
«php_cs_fixer_on_save»: false,
«php_cs_fixer_show_quick_panel»: true,
«phpcbf_additional_args»:
{
«—standard»: «PSR2»,
«-n»: «»
},
«phpcbf_executable_path»: «/usr/local/php5/bin/phpcbf»,
«phpcbf_on_save»: false,
«phpcbf_show_quick_panel»: true,
«phpcs_additional_args»:
{
«—standard»: «PSR2»,
«-n»: «»
},
«phpcs_command_on_save»: false,
«phpcs_executable_path»: «/usr/local/php5/bin/phpcs»,
«phpcs_execute_on_save»: false,
«phpcs_icon_scope_color»: «comment»,
«phpcs_linter_command_on_save»: false,
«phpcs_linter_regex»: «(?P.*) on line (?Pd+)»,
«phpcs_linter_run»: true,
«phpcs_outline_for_errors»: true,
«phpcs_php_path»: «/usr/local/php5/bin/php»,
«phpcs_show_errors_in_status»: true,
«phpcs_show_errors_on_save»: true,
«phpcs_show_gutter_marks»: true,
«phpcs_show_quick_panel»: true,
«phpcs_sniffer_run»: true,
«phpmd_additional_args»:
{
«codesize,unusedcode,naming»: «»
},
«phpmd_command_on_save»: false,
«phpmd_executable_path»: «/usr/local/php5/bin/phpmd»,
«phpmd_run»: true,
«save_on_focus_lost»: true,
«scheck_additional_args»:
{
«-strict»: «»
},
«scheck_command_on_save»: false,
«scheck_executable_path»: «»,
«scheck_run»: false,
«scroll_past_end»: true,
«show_debug»: false,
«tab_size»: 4,
«translate_tabs_to_spaces»: true
}

Is there a config error ?

Thanks.