Trying to take output of a code and pass it to another statement.

```
t = ", ".join(DTYPE)
output = ('data', list), ('freq', str)

```

Would like to using "output" and pass into the following:

```
DF_TYPE = numpy.dtype([t)])
DF = numpy.empty(0, dtype=DF_TYPE)

```

That is, evaluate

```
DF_TYPE = numpy.dtype([('data', list), ('freq', str)])
DF = numpy.empty(0, dtype=DF_TYPE)

```

Error received:

```
Exception has occurred: TypeError
data type not understood

```

Sample data:

```
JSON_DATA = {
  "data": [
    {
      "Members": 29,
      "period": "2020-06-30",
      "TCOC": 5880070,
    },
    {
      "Members": 21,
      "period": "2020-03-31",
      "TCOC": 5689074,
    }
  ],
  "freq": "quarterly"
}

```

Have tried using exec() and eval() to no avail.