# Code that creates a list of 100 'heads' or 'tails' values.
    results.append(random.choice(('H', 'T')))

This comment is severely misleading: the code does not create a list of 100 values, it create an infinitely growing list that extends up to sampleSize values by the time the program terminates.

Independently of the misleading comment, this is a bad idea, and can be avoided by limiting the size of the results list in some say (del results[:-6], or results = results[-6:], I'm not sure which is better). This would also obsolete the temp variable, because the results array would no longer contain extra flips.

    try:
        temp = results[i-5:]
        if temp == head_streak or temp == tail_streak:
            numberOfStreaks += 1
    except:
        pass

Bare except statements are a bad idea. Bare except:pass statements even more so. Among other problems, it means that if you press Ctrl-C while your code is executing that section, the code won't exit.

It's not clear what exception you are trying to catch (results[i-5:] doesn't throw an error if results is less than five columns long; it just truncates the list), so I can't suggest a direct replacement, but I would recommend either catching a specific exception, or removing the try-catch entirely.

Python lists natively support negative indexing, so you can simplify results[i-5:] to results[-6:] and remove the i variable entirely. As suggested by the question asker in the comments, this makes the enumerate call unnecessary.

The i variable will then be unused. It's clearer to name variables you don't use as _, so it's easy to tell that they aren't used.

Full code:

import random
numberOfStreaks = 0
results = []
head_streak = ['H'] * 6
tail_streak = ['T'] * 6
sample_size = 1000000
for _ in range(sample_size):
    # Code that generates another 'heads' or 'tails' value
    results.append(random.choice(('H', 'T')))

    # Code that checks if there is a streak of 5 heads or tails in a row.
    results = results[-6:]
    if results == head_streak or results == tail_streak:
        numberOfStreaks += 1

print('Chance of streak: %s%%' % (numberOfStreaks / sample_size))

    # Code that creates a list of 100 'heads' or 'tails' values.
    results.append(random.choice(('H', 'T')))

This comment is severely misleading: the code does not create a list of 100 values, it create an infinitely growing list that extends up to sampleSize values by the time the program terminates.

Independently of the misleading comment, this is a bad idea, and can be avoided by limiting the size of the results list in some say (del results[:-6], or results = results[-6:], I'm not sure which is better). This would also obsolete the temp variable, because the results array would no longer contain extra flips.

    try:
        temp = results[i-5:]
        if temp == head_streak or temp == tail_streak:
            numberOfStreaks += 1
    except:
        pass

Bare except statements are a bad idea. Bare except:pass statements even more so. Among other problems, it means that if you press Ctrl-C while your code is executing that section, the code won't exit.

It's not clear what exception you are trying to catch (results[i-5:] doesn't throw an error if results is less than five items long; it just truncates the list), so I can't suggest a direct replacement, but I would recommend either catching a specific exception, or removing the try-catch entirely.

Python lists natively support negative indexing, so you can simplify results[i-5:] to results[-6:] and remove the i variable entirely. As suggested by the question asker in the comments, this makes the enumerate call unnecessary.

The i variable will then be unused. It's clearer to name variables you don't use as _, so it's easy to tell that they aren't used.

Full code:

import random
numberOfStreaks = 0
results = []
head_streak = ['H'] * 6
tail_streak = ['T'] * 6
sample_size = 1000000
for _ in range(sample_size):
    # Code that generates another 'heads' or 'tails' value
    results.append(random.choice(('H', 'T')))

    # Code that checks if there is a streak of 5 heads or tails in a row.
    results = results[-6:]
    if results == head_streak or results == tail_streak:
        numberOfStreaks += 1

print('Chance of streak: %s%%' % (numberOfStreaks / sample_size))

    # Code that creates a list of 100 'heads' or 'tails' values.
    results.append(random.choice(('H', 'T')))

This comment is severely misleading: the code does not create a list of 100 values, it create an infinitely growing list that extends up to sampleSize values by the time the program terminates.

Independently of the misleading comment, this is a bad idea, and can be avoided by limiting the size of the results list in some say (del results[:-6], or results = results[-6:], I'm not sure which is better). This would also obsolete the temp variable, because the results array would no longer contain extra flips.

    try:
        temp = results[i-5:]
        if temp == head_streak or temp == tail_streak:
            numberOfStreaks += 1
    except:
        pass

Bare except statements are a bad idea. Bare except:pass statements even more so. Among other problems, it means that if you press Ctrl-C while your code is executing that section, the code won't exit.

It's not clear what exception you are trying to catch (results[i-5:] doesn't throw an error if results is less than five columns long; it just truncates the list), so I can't suggest a direct replacement, but I would recommend either catching a specific exception, or removing the try-catch entirely.

Python lists natively support negative indexing, so you can simplify results[i-5:] to results[-6:] and remove the i variable entirely.

You don't appear to use the experimentNumber variable. It's clearer to name variables you don't use as _, so it's easy to tell that they aren't used.

Full code:

import random
numberOfStreaks = 0
results = []
head_streak = ['H'] * 6
tail_streak = ['T'] * 6
sample_size = 1000000
for i, _ in enumerate(range(sample_size)):
    # Code that generates another 'heads' or 'tails' value
    results.append(random.choice(('H', 'T')))

    # Code that checks if there is a streak of 5 heads or tails in a row.
    results = results[-6:]
    if results == head_streak or results == tail_streak:
        numberOfStreaks += 1

print('Chance of streak: %s%%' % (numberOfStreaks / sample_size))

    # Code that creates a list of 100 'heads' or 'tails' values.
    results.append(random.choice(('H', 'T')))

This comment is severely misleading: the code does not create a list of 100 values, it create an infinitely growing list that extends up to sampleSize values by the time the program terminates.

Independently of the misleading comment, this is a bad idea, and can be avoided by limiting the size of the results list in some say (del results[:-6], or results = results[-6:], I'm not sure which is better). This would also obsolete the temp variable, because the results array would no longer contain extra flips.

    try:
        temp = results[i-5:]
        if temp == head_streak or temp == tail_streak:
            numberOfStreaks += 1
    except:
        pass

Bare except statements are a bad idea. Bare except:pass statements even more so. Among other problems, it means that if you press Ctrl-C while your code is executing that section, the code won't exit.

It's not clear what exception you are trying to catch (results[i-5:] doesn't throw an error if results is less than five columns long; it just truncates the list), so I can't suggest a direct replacement, but I would recommend either catching a specific exception, or removing the try-catch entirely.

Python lists natively support negative indexing, so you can simplify results[i-5:] to results[-6:] and remove the i variable entirely. As suggested by the question asker in the comments, this makes the enumerate call unnecessary.

The i variable will then be unused. It's clearer to name variables you don't use as _, so it's easy to tell that they aren't used.

Full code:

import random
numberOfStreaks = 0
results = []
head_streak = ['H'] * 6
tail_streak = ['T'] * 6
sample_size = 1000000
for _ in range(sample_size):
    # Code that generates another 'heads' or 'tails' value
    results.append(random.choice(('H', 'T')))

    # Code that checks if there is a streak of 5 heads or tails in a row.
    results = results[-6:]
    if results == head_streak or results == tail_streak:
        numberOfStreaks += 1

print('Chance of streak: %s%%' % (numberOfStreaks / sample_size))