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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 fetch_logs_from_host(hostname, install_path, prefix, logs, directory, pattern):
 """ Static method Copies logs from specified host on the specified install path :Parameter hostname the remote host from where we need to fetch the logs :Parameter install_path path where the app is installed :Parameter prefix prefix used to copy logs. Generall the unique_id of process :Parameter logs a list of logs given by absolute path from the remote host :Parameter directory the local directory to store the copied logs :Parameter pattern a pattern to apply to files to restrict the set of logs copied """

    if hostname is not None:
      with get_sftp_client(hostname, username=runtime.get_username(), password=runtime.get_password()) as ftp:
        for f in logs:
          try:
            mode = ftp.stat(f).st_mode
          except IOError, e:
            if e.errno == errno.ENOENT:
              logger.error("Log file " + f + " does not exist on " + hostname)
              pass
          else:
            copy_dir(ftp, f, directory, prefix)
        if install_path is not None:
          copy_dir(ftp, install_path, directory, prefix, pattern)