Added a description

Unfortunately, I don't understand what you mean.

I set conditions on this kata that are described.

According to these conditions need to provide a working code.

All these conditions are verified by tests

Could you more details to explain what you mean, please?

The function doesn't return 1 and he expected result is not 2. 1 should equal 2 doesn't make sense.

I replaced the 'assert_true' with 'assert_equals'.

Also, I do not understand what you mean about
"Python: useless error messages:"

1 should equal 2

Python: useless error messages:

1 should equal 2

"module 'codewars_test' has no attribute 'assert_true'" should equal 'Duplicate UIDs'

Made more numbers of tests

1 test is not adequate. Typically there should be around 100 tests.

Added description

Added test which has an array of various lengths with random values at the input

This code should be working with commands IDs
Which IDs were input in the variable $uids they should be returned as an array certain configuration, this is one of the rules.
You showed me an array in which there are values ​​that should not be there

The new test case return very cryptic expected/actual results because it is performing a complicated check, such as

Failed asserting that two arrays are equal.
Expected: Array (
    0 => 61
    1 => 110
    2 => 122
    3 => 124
    4 => 129
    5 => 139
    6 => 142
    7 => 152
    8 => 165
    9 => 179
    10 => 180
    11 => 214
    12 => 280
    13 => 312
    14 => 412
    15 => 445
    16 => 521
    17 => 712
    18 => 845
    19 => 911
    20 => 1219
)
Actual  : Array (
    0 => 1
    1 => 2
    2 => 3
    3 => 4
    4 => 5
    5 => 6
    6 => 7
    7 => 8
    8 => 9
    9 => 10
    10 => 11
    11 => 12
    12 => 13
    13 => 14
    14 => 15
    15 => 16
    16 => 17
    17 => 18
    18 => 19
    19 => 20
    20 => 21
    21 => 61
    22 => 110
    23 => 122
    24 => 124
    25 => 129
    26 => 139
    27 => 142
    28 => 152
    29 => 165
    30 => 179
    31 => 180
    32 => 214
    33 => 280
    34 => 312
    35 => 412
    36 => 445
    37 => 521
    38 => 712
    39 => 845
    40 => 911
    41 => 1219
)

Similarly, $this->assertTrue($unique); is not acceptable: if a test case fails there are no indication why it failed, which provides no useful (to downright misleading) feedback.

There are still no random tests. There was only a fixed test added.

The required input validation and what should be done about them (including throwing an exception with a specific message) should be all in the description. It is a key part of the spec.

After resolving the issues you need to republish the kata as well. It's currently in draft.