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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fingerprint_from_keybase(fingerprint, kb_obj):
 """Extracts a key matching a specific fingerprint from a Keybase API response"""

    if 'public_keys' in kb_obj and \
       'pgp_public_keys' in kb_obj['public_keys']:
        for key in kb_obj['public_keys']['pgp_public_keys']:
            keyprint = fingerprint_from_var(key).lower()
            fingerprint = fingerprint.lower()
            if fingerprint == keyprint or \
               keyprint.startswith(fingerprint) or \
               keyprint.endswith(fingerprint):
                return {
                    'fingerprint': keyprint,
                    'bundle': key
                }

    return None