Python keyword not valid identifier in numexpr query

The "Python keyword not valid identifier" error in a numexpr query occurs when you use a Python keyword as a variable name in the query. Numexpr is a library that allows you to evaluate numerical expressions in a fast and efficient way. Here's an example of how this error might occur:

import numexpr as ne

x = 10
y = 20
z = ne.evaluate('if else(x > y, x, y)')

In this example, the 'if' and 'else' keywords are used as variable names in the numexpr query. To fix this error, you should choose different variable names that do not conflict with Python keywords. Here's the corrected code:

import numexpr as ne

x = 10
y = 20
z = ne.evaluate('where(x > y, x, y)')

In this corrected code, the 'if' and 'else' keywords have been replaced with the 'where' keyword, which is a valid numexpr function.