Convert a string to preexisting variable names

Note: do not use eval in any case where you are getting the name to look up from user entered input. For example, if this comes from a web page, there is nothing preventing anyone from entering:

__import__("os").system("Some nasty command like rm -rf /*")

as the argument. Better is to limit to well-defined lookup locations such as a dictionary or instance using getattr(). For example, to find the "post" value on self, use:

varname = "post"
value = getattr(self, varname)  # Gets self.post

Similarly to set it, use setattr():

value = setattr(self, varname, new_value)

To handle fully qualified names, like "post.id", you could use something like the below functions in place of getattr() / setattr().

def getattr_qualified(obj, name):
    for attr in name.split("."):
        obj = getattr(obj, attr)
    return obj

def setattr_qualified(obj, name, value):
    parts = name.split(".")
    for attr in parts[:-1]:
        obj = getattr(obj, attr)
    setattr(obj, parts[-1], value)

Also, there is the globals() function in Python which returns a dictionary with all the defined variables. You could also use something like this:

print globals()["myvar"]

You could do something like what Geo recommended, or go with:

>>> wine = 'pinot_noir'
>>> vars()[wine] = 'yum'
>>> pinot_noir
'yum'

Note: vars() and globals() are the same, I'm just used to using vars() I'm surprised nobody called me out on this! Anyway, it's vars() and locals() that are the same.

Use this

var="variable name"
def returnvar(string):
    exec(f"""global rtn
rtn={string}""")
    return rtn

var will be your string and run returnvar(var) will to return variable