In mathematics, a **pandigital number** is a number that in a given base has among its significant digits each digit used in the base at least once. For example, 1234567890 is a pandigital number in base 10.
For simplification, in this kata, we will consider pandigital numbers in *base 10* and with all digits used *exactly once*. The challenge is to calculate a sorted sequence of pandigital numbers, starting at a certain `offset` and with a specified `size`.
Example:
```python
  > get_sequence(0, 5)
  [1023456789, 1023456798, 1023456879, 1023456897, 1023456978]
```
Rules:
- We are looking for positive pandigital numbers in base 10.
- Each digit should occur `exactly once`.
- A pandigital number can't start with digit zero.
- The offset is an integer (negative, zero or positive number) (long in Java)
- The size is a positive integer number (int in Java)
- Return the `size` pandigital numbers which are not smaller than the `offset`. If there is not enough `size` pandigital numbers, just return all of them.
- Return an empty array if nothing is found.
def get_sequence(o,s,st=1023456789):
    li = []
    for i in range([st,o][o>0 and o>st],9876543211):
        i = str(i)
        if i[0]!='0' and len(set(i))==10 : li.append(int(i))
        if len(li)==s : break
    return li 
def get_sequence(o,s,st=1023456789):
    li = []
    for i in range([st,o][o>0 and o>st],9876543211):
        i = str(i)
        if i[0]!='0' and len(set(i))==10 : li.append(int(i))
        if len(li)==s : break
    return li 