QST:What is the largest datetime in pandas to_datetime?
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#### Question about pandas

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I am  trying to read a date from excel. For validation, when I use 'pd.to_datetime' to compare against another datetime object, for date 9999-12-31, I am getting an exception: 'OutofBoundsDateTime', whereas I believe this should still be a valid MAXDATE as per standards. Here is a sample code where I am facing such issue:

```python
# Your code here, if applicable
import pandas as pd
df = pd.DataFrame(["9999-12-31"])
pd.to_datetime(df[0])
```
