title: Get ethereum address from secpk256 public key not generated using geth crypto package
body: <p>I have a public key that gets generated using the secpk256 curve, I am trying to determine the ethereum address of this public key. Basically I obtain the key as a simple string and then try to use geths crypto functions to get the public address of this public key. </p>
  
  <p>Heres a sample hex encoded public key string: 
  02ccb8bc17397c55242a27d1681bf48b5b40a734205760882cd83f92aca4f1cf45
  heres my code sample: </p>
  
  <pre><code>package main
  
  import (
      "github.com/ethereum/go-ethereum/crypto"
  )
  
  
  publickey := "02ccb8bc17397c55242a27d1681bf48b5b40a734205760882cd83f92aca4f1cf45"
  ecdsaPub, err := crypto.UnmarshalPubkey(publickey)
  if err != nil {
      return "", err
  }
  ethAddress := crypto.PubkeyToAddress(*ecdsaPub).String()
  </code></pre>