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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 _broadcast_compat_variables(*variables):
 """Create broadcast compatible variables, with the same dimensions. Unlike the result of broadcast_variables(), some variables may have dimensions of size 1 instead of the the size of the broadcast dimension. """

    dims = tuple(_unified_dims(variables))
    return tuple(var.set_dims(dims) if var.dims != dims else var
                 for var in variables)