user131468: I've searched really hard for a Python script that coverts a compressed public key into uncompressed one, since I don't know how to code this.
I stumbled upon these links:
https://stackoverflow.com/questions/43629265/deriving-an-ecdsa-uncompressed-public-key-from-a-compressed-one
How to uncompress a public key?
https://bitcointalk.org/index.php?topic=644919.0
but all python scripts/functions either don't work or outputting incorrect values. I tried to debug them and failed.
Could you point out how to code something like this in Python or give an example of the working code?
Here are the values to play with (HEX):
#Test case 1
#Compressed Pubkey: 025A2146590B80D1F0D97CC7104E702011AFFF21BFAF817F5C7002446369BA9DDC
'''
Right Uncompressed Pubkey:
045A2146590B80D1F0D97CC7104E702011AFFF21BFAF817F5C7002446369BA9DDC9BD5DCD1B4A737244D6BB7B96E256391B8597D3A7972A6F8CA9096D4AEA1F37E
'''

#Test case 2
#Compressed Pubkey: 035728F4692D85D411DF3643CD69FE05C411A0D507C7D814008F56C8F260AD7ED9
'''
Right Uncompressed Pubkey:
045728F4692D85D411DF3643CD69FE05C411A0D507C7D814008F56C8F260AD7ED99E2DF8D9CB1A575D55264692629AE22E518BC14AD02592941C13BE6755C72973
'''

#Test case 3
#Compressed Pubkey:039E87EB177890FDD788B95843ED53AD4FB6E877E3F730EF1E73593964C2AB9D15
'''
Right Uncompressed Pubkey:
049E87EB177890FDD788B95843ED53AD4FB6E877E3F730EF1E73593964C2AB9D15A3B647C8C4A0766420917B7B445CDCD6BFEC2900175C5534C6113954F3FF00D9
'''


user76567: Using this library (disclaimer: I am the author):
>>> from cryptotools import PublicKey

>>> PublicKey.from_hex('025A2146590B80D1F0D97CC7104E702011AFFF21BFAF817F5C7002446369BA9DDC').hex(compressed=False)
'045a2146590b80d1f0d97cc7104e702011afff21bfaf817f5c7002446369ba9ddc9bd5dcd1b4a737244d6bb7b96e256391b8597d3a7972a6f8ca9096d4aea1f37e'



131468: <p>I've searched really hard for a Python script that coverts a compressed public key into uncompressed one, since I don't know how to code this.
I stumbled upon these links:</p>
<p><a href="https://stackoverflow.com/questions/43629265/deriving-an-ecdsa-uncompressed-public-key-from-a-compressed-one">https://stackoverflow.com/questions/43629265/deriving-an-ecdsa-uncompressed-public-key-from-a-compressed-one</a></p>
<p><a href="https://bitcoin.stackexchange.com/questions/86234/how-to-uncompress-a-public-key">How to uncompress a public key?</a></p>
<p><a href="https://bitcointalk.org/index.php?topic=644919.0" rel="nofollow noreferrer">https://bitcointalk.org/index.php?topic=644919.0</a></p>
<p>but all python scripts/functions either don't work or outputting incorrect values. I tried to debug them and failed.
Could you point out how to code something like this in Python or give an example of the working code?
Here are the values to play with (HEX):</p>
<pre><code>#Test case 1
#Compressed Pubkey: 025A2146590B80D1F0D97CC7104E702011AFFF21BFAF817F5C7002446369BA9DDC
'''
Right Uncompressed Pubkey:
045A2146590B80D1F0D97CC7104E702011AFFF21BFAF817F5C7002446369BA9DDC9BD5DCD1B4A737244D6BB7B96E256391B8597D3A7972A6F8CA9096D4AEA1F37E
'''

#Test case 2
#Compressed Pubkey: 035728F4692D85D411DF3643CD69FE05C411A0D507C7D814008F56C8F260AD7ED9
'''
Right Uncompressed Pubkey:
045728F4692D85D411DF3643CD69FE05C411A0D507C7D814008F56C8F260AD7ED99E2DF8D9CB1A575D55264692629AE22E518BC14AD02592941C13BE6755C72973
'''

#Test case 3
#Compressed Pubkey:039E87EB177890FDD788B95843ED53AD4FB6E877E3F730EF1E73593964C2AB9D15
'''
Right Uncompressed Pubkey:
049E87EB177890FDD788B95843ED53AD4FB6E877E3F730EF1E73593964C2AB9D15A3B647C8C4A0766420917B7B445CDCD6BFEC2900175C5534C6113954F3FF00D9
'''
</code></pre>
 76567: <p>Using <a href="https://github.com/mcdallas/cryptotools" rel="nofollow noreferrer">this</a> library (disclaimer: I am the author):</p>
<pre><code>&gt;&gt;&gt; from cryptotools import PublicKey

&gt;&gt;&gt; PublicKey.from_hex('025A2146590B80D1F0D97CC7104E702011AFFF21BFAF817F5C7002446369BA9DDC').hex(compressed=False)
'045a2146590b80d1f0d97cc7104e702011afff21bfaf817f5c7002446369ba9ddc9bd5dcd1b4a737244d6bb7b96e256391b8597d3a7972a6f8ca9096d4aea1f37e'

</code></pre>
