[Python] Why get unexpected dict

I have a data table as below:

A B C
type1 A1 B1 C1
type2 A2 B2 C2


I use the code below

d={}
D={}
h = ['A','B','C']
type1=['A1','B1','C1']
type2=['A2','B2','C2']

for i,val in enumerate(h):

d['Type1'] = type1
d['Type2'] = type2
D[val]=d
print('loop',i,'\nd:',d,'\nD:',D,'\n\n====')

#print(D)


I would expect to get the following dict as result:

{'A':{'Type1':'A1','Type2':'A2'},'B':{'Type1':'B1','Type2':B2},'C':{'Type1':C1,'Type2':'C2'},}


However, the output is:

{'A': {'Type1': 'C1', 'Type2': 'C2'}, 'B': {'Type1': 'C1', 'Type2': 'C2'}, 'C': {'Type1': 'C1', 'Type2': 'C2'}}


What's the error in my logic?

I can't figure out what's wrong there.

I added a print in the loop.

loop 0
d: {'Type1': 'A1', 'Type2': 'A2'}
D: {'A': {'Type1': 'A1', 'Type2': 'A2'}}

====
loop 1
d: {'Type1': 'B1', 'Type2': 'B2'}
D: {'A': {'Type1': 'B1', 'Type2': 'B2'}, 'B': {'Type1': 'B1', 'Type2': 'B2'}}

====
loop 2
d: {'Type1': 'C1', 'Type2': 'C2'}
D: {'A': {'Type1': 'C1', 'Type2': 'C2'}, 'B': {'Type1': 'C1', 'Type2': 'C2'}, 'C': {'Type1': 'C1', 'Type2': 'C2'}}

====


from the output, the d is correct in every loop But D is getting changed in very loop! Not sure why it would be in that way.

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