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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 _parse_decimal(buf):
 """Parses the remainder of a file-like object as a decimal."""

    exponent = _parse_var_int(buf, signed=True)
    sign_bit, coefficient = _parse_signed_int_components(buf)

    if coefficient == 0:
        # Handle the zero cases--especially negative zero
        value = Decimal((sign_bit, (0,), exponent))
    else:
        coefficient *= sign_bit and -1 or 1
        value = Decimal(coefficient).scaleb(exponent)

    return value