feat(rust, python): improve datetime parsing error message

[MarcoGorelli]

Demo

On main:

In [1]: pl.Series(['2020-01-01', '2020-01-o2']).str.to_date()
---------------------------------------------------------------------------
ComputeError: strict date parsing failed for 1 value(s) (1 unique): ["2020-01-o2"]

You might want to try:
- setting `strict=False`
- explicitly specifying a `format`

In [2]: pl.Series(['2020-01-01', '2020-01-o2']).str.to_date(format='%Y-%m-%d')
---------------------------------------------------------------------------
ComputeError: strict date parsing failed for 1 value(s) (1 unique): ["2020-01-o2"]

You might want to try:
- setting `strict=False`
- explicitly specifying a `format`

In [3]: pl.Series(['00:00', '00:0l']).str.to_time(format='%H:%M')
---------------------------------------------------------------------------
ComputeError: strict time parsing failed for 1 value(s) (1 unique): ["00:0l"]

You might want to try:
- setting `strict=False`
- explicitly specifying a `format`

Here:

In [1]: pl.Series(['2020-01-01', '2020-01-o2']).str.to_date()
---------------------------------------------------------------------------
ComputeError: strict date parsing failed for 1 value(s) (1 unique): ["2020-01-o2"]

You might want to try:
- setting `strict=False`
- setting `exact=False` (note: this is much slower!)
- explicitly specifying `format`

In [2]: pl.Series(['2020-01-01', '2020-01-o2']).str.to_date(format='%Y-%m-%d')
---------------------------------------------------------------------------
ComputeError: strict date parsing failed for 1 value(s) (1 unique): ["2020-01-o2"]

You might want to try:
- setting `strict=False`
- setting `exact=False` (note: this is much slower!)
- checking whether the format provided ('%Y-%m-%d') is correct

In [3]: pl.Series(['00:00', '00:0l']).str.to_time(format='%H:%M')
---------------------------------------------------------------------------
ComputeError: strict time parsing failed for 1 value(s) (1 unique): ["00:0l"]

You might want to try:
- setting `strict=False`
- checking whether the format provided ('%H:%M') is correct

[ritchie46]

Very nice!

[MarcoGorelli]

thanks! 🙏