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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 _build_width_map():
 """ Build a translate mapping that replaces halfwidth and fullwidth forms with their standard-width forms. """

    # Though it's not listed as a fullwidth character, we'll want to convert
    # U+3000 IDEOGRAPHIC SPACE to U+20 SPACE on the same principle, so start
    # with that in the dictionary.
    width_map = {0x3000: ' '}
    for i in range(0xff01, 0xfff0):
        char = chr(i)
        alternate = unicodedata.normalize('NFKC', char)
        if alternate != char:
            width_map[i] = alternate
    return width_map