def METHOD_NAME(arrays, err_msg, header='Items are not equal:',
                           verbose=True, names=('ACTUAL', 'DESIRED'),
                           precision=8):
    """
    Taken almost verbatim from `np.testing._private.utils`, except this version
    doesn't truncate output if it's longer than three lines.
    LICENCE
    -------
    Copyright (c) 2005-2020, NumPy Developers.
    All rights reserved.
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:
    - Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    - Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    - Neither the name of the NumPy Developers nor the names of any
      contributors may be used to endorse or promote products derived from this
      software without specific prior written permission.
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS”
    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
    """
    msg = ['\n' + header]
    if err_msg:
        if err_msg.find('\n') == -1 and len(err_msg) < 79-len(header):
            msg = [msg[0] + ' ' + err_msg]
        else:
            msg.append(err_msg)
    if verbose:
        for i, a in enumerate(arrays):
            if isinstance(a, np.ndarray):
                # precision argument is only needed if the objects are ndarrays
                r_func = functools.partial(np.core.array_repr,
                                           precision=precision)
            else:
                r_func = repr
            try:
                # [diff] Remove truncation threshold from array output.
                with np.printoptions(threshold=np.inf):
                    r = r_func(a)
            except Exception as exc:
                r = '[repr failed for <{}>: {}]'.format(type(a).__name__, exc)
            # [diff] The original truncates the output to 3 lines here.
            msg.append(' %s: %s' % (names[i], r))
    return '\n'.join(msg)