In course "Python Core" Code project 91 - Phone Number Validator

Question

In course "Python Core" Code project 91 - Phone Number Validator
2 variants of code behaves strangely at https://www.sololearn.com/learning/eom-project/1073/356
1 variant Code
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import re
#your code goes here
pattern = r"\A[189][0-9][0-9][0-9][0-9][0-9][0-9][0-9]\Z"

if re.match(pattern, "57345672"):
print ("Valid")
else:
print ("Invalid")
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and
2 variant
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import re
#your code goes here
pattern = r"[189]\d{7}

Answer 1

It's "1" or "8" or "9":
[1|8|9]

Answer 2

Thanks for your wise advice Simon, sorry for stupid mistake

Answer 3

There's nothing stupid about this. It takes time to memorise these things.

Answer 4

import re
num = input ()
pattern = r"^[1|8|9][0-9]*quot;
if re.match(pattern,num) and len(num)==8:
print("Valid")
else:
print("Invalid")