Keyerror: ‘key of type tuple not found and not a multiindex’

When you encounter the error “keyerror: ‘key of type tuple not found and not a multiindex'” in Python, it means that you are trying to access a key which is either not present in the dictionary or that you are using a tuple as a key instead of a single value or a multi-index.

To understand this error better, let’s look at an example:

# Creating a simple dictionary
my_dict = {'key1': 'value1', 'key2': 'value2'}

# Accessing a non-existent key
print(my_dict['key3'])  # Raises a KeyError

In the above example, we are trying to access the key ‘key3’ from the dictionary, which does not exist. This results in a KeyError. To avoid this error, make sure the dictionary contains the key you are trying to access.

Now let’s take a look at an example involving a tuple key and a multi-index:

# Creating a dictionary with a tuple key
my_dict = {('key1', 'key2'): 'value1', ('key3', 'key4'): 'value2'}

# Accessing a tuple key
print(my_dict[('key1', 'key2')])  # Outputs 'value1'

# Accessing a non-existent tuple key
print(my_dict[('key5', 'key6')])  # Raises a KeyError

In this example, we have a dictionary with tuple keys. The key (‘key1’, ‘key2’) exists in the dictionary, so accessing it returns the corresponding value ‘value1’. However, if we try to access a tuple key that does not exist, such as (‘key5’, ‘key6’), a KeyError is raised.

The error message indicates that the key being used should be of type tuple, but it was not found in the dictionary. If you encounter this error, double-check the keys you are using and ensure they exist in the dictionary or that you are using the correct indexing method for multi-index keys.