Error with eval() function with print function in python

Question

I am trying to run this in Python IDLE:

>>> eval(print("123*13"))

I get the output correctly, but it comes with a TypeError:

123*13
Traceback (most recent call last):
  File "<pyshell#4>", line 1, in <module>
    eval(print("123*13"))
TypeError: eval() arg 1 must be a string, bytes or code object

NOTE:
I do NOT want to do print(eval("123*13")).
I want to use print() in eval() function. This is NOT for actual implementation, but I got this error while using eval() function. I am not asking this for any actual implementation, but curiosity.

So, will a function in `eval()` always throw an error if it returns `None`? — CoolCoder, May 06 '21 at 01:49
Related: [How is returning the output of a function different from printing it?](https://stackoverflow.com/q/750136/4518341) — wjandrea, May 06 '21 at 01:49
Why are you using `eval()` in the first place? Like, what are you actually trying to accomplish? This seems like an [XY problem](https://meta.stackexchange.com/q/66377/343832). Please [edit] to clarify. It'd be best to put it in the form of a question. See [ask] if you want more tips. — wjandrea, May 06 '21 at 01:55
@wjandrea, no, this is exactly where I was stuck, and not like XYproblem — CoolCoder, May 06 '21 at 03:32
@ShubhamPeriwal, no, I did not mean that. I have updated the question — CoolCoder, May 06 '21 at 03:36
@CoolCoder But why? If the string is also in source code, why not just do `print("123*13")`? — wjandrea, May 06 '21 at 03:37

score 3 · Accepted Answer · 2021-05-14T16:36:31.010

Use it:

eval('print("123*13")')

in eval() src:

evel (__source: str | bytes | CodeType, __globals: Dict[str, Any] | None = ..., __locals: Mapping[str, Any] | None = ...) -> Any
'''Evaluate the given source in the context of globals and locals.

The source may be a string representing a Python expression    
or a code object as returned by compile().
The globals must be a dictionary and locals can be any mapping,
defaulting to the current globals and locals.
If only globals is given, locals defaults to it.'''
...

eval help():

eval(source, globals=None, locals=None, /)
    Evaluate the given source in the context of globals and locals.

    The source may be a string representing a Python expression
    or a code object as returned by compile().
    The globals must be a dictionary and locals can be any mapping,
    defaulting to the current globals and locals.
    If only globals is given, locals defaults to it.

You can see more in Python.org.

Thank you @Delta for the answer. It seems that `eval()` function needs only `str` as input, so the `print()` function too must be as a `str`. — CoolCoder, May 14 '21 at 15:06
str formats: `'''str''', """str""", 'str', "str", '\'str\'', ... — , May 14 '21 at 16:29

Error with eval() function with print function in python

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