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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 _agl_compliant_name(glyph_name):
 """Return an AGL-compliant name string or None if we can't make one."""

    MAX_GLYPH_NAME_LENGTH = 63
    clean_name = re.sub("[^0-9a-zA-Z_.]", "", glyph_name)
    if len(clean_name) > MAX_GLYPH_NAME_LENGTH:
        return None
    return clean_name