QST:  DatetimeIndex changes
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#### Question about pandas

In version 1.0.5, DatetimeIndex seems greatly changed from earlier versions 
Was this intentional and documented in the version changes?

Many statsmodels  forecasting steps now break
 
For example, the code below no longer works

dx = pd.DatetimeIndex(start ='2020-01-01 00:00', freq ='M',  periods = 12)

I get
 TypeError: __new__() got an unexpected keyword argument 'start'

The documentation has these arguments 

 class pandas.DatetimeIndex(data=None, freq=None, tz=None, normalize=False, closed=None, ambiguous='raise', dayfirst=False, yearfirst=False, dtype=None, copy=False, name=None)[source]

with little explanation or usefulness IMHO 

I see old Pandas has 
def __new__(cls, data=None,
                freq=None, start=None, end=None, periods=None, tz=None,
                normalize=False, closed=None, ambiguous='raise',
                dayfirst=False, yearfirst=False, dtype=None,
                copy=False, name=None, verify_integrity=True): 

```python

# Your code here, if applicable
# Create the DatetimeIndex 
dx = pd.DatetimeIndex(start ='2020-01-01 00:00', freq ='M',  periods = 12)
## expect TypeError: __new__() got an unexpected keyword argument 'start'

```
