with open('text.txt') as f:
    text = f.read()
compressed_keys = text.split('\n')
 
uncompressed_keys = []
 
p = 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2f
for compressed_key in compressed_keys:
 y_parity = int(compressed_key[:2]) - 2
x = int(compressed_key[2:], 16)
a = (pow_mod(x, 3, p) + 7) % p
y = pow_mod(a, (p+1)//4, p)
if y % 2 != y_parity:
 y = -y % p
uncompressed_key = '04{:x}{:x}'.format(x, y)
uncompressed_keys.append(uncompressed_key)
with open('result.txt', 'w') as f:
 f.write('\n'.join(uncompressed_keys))

 Traceback (most recent call last):
  File "D:\bit\A2\02\PubKey_04txt6.py", line 9, in <module>
    y_parity = int(compressed_key[:2]) - 2
ValueError: invalid literal for int() with base 10: ''

  
>>> compressed_keys = '\ne7\n'.split('\n')
>>> compressed_keys
['', 'e7', '']
>>> compressed_keys = [i for i in '\ne7\n'.split('\n') if i]
>>> compressed_keys
['e7']
>>>

  
>>> int('e7')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: 'e7'
>>> int('e7', 16)
231
>>>

 with open('text.txt') as f:
    text = f.read()
compressed_keys = text.split('\n')
uncompressed_keys = []
p = 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2f
for compressed_key in compressed_keys:
 y_parity = int(compressed_key[:2]) - 2
x = int(compressed_key[2:], 16)
a = (pow_mod(x, 3, p) + 7) % p
y = pow_mod(a, (p+1)//4, p)
if y % 2 != y_parity:
 y = -y % p
uncompressed_key = '04{:x}{:x}'.format(x, y)
uncompressed_keys.append(uncompressed_key)
with open('result.txt', 'w') as f:
 f.write('\n'.join(uncompressed_keys))