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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 get_keypair_fn():
 """Location of .pem file for current keypair"""


  keypair_name = get_keypair_name()
  account = get_account_number()
  region = get_region()
  fn = f'{PRIVATE_KEY_LOCATION}/{keypair_name}-{account}-{region}.pem'
  return fn