This project contains tasks for learning to use variable/type annotations in Python 3.

• 0. Basic annotations - add
  0-add.py contains a type-annotated function add that takes a float a and a float b as arguments and returns their sum as a float..

• 1. Basic annotations - concat
  1-concat.py contains a type-annotated function concat that takes a string str1 and a string str2 as arguments and returns a concatenated string.

• 2. Basic annotations - floor
  2-floor.py contains a type-annotated function floor which takes a float n as argument and returns the floor of the float.

• 3. Basic annotations - to string
  3-to_str.py contains a type-annotated function to_str that takes a float n as argument and returns the string representation of the float.

• 4. Define variables
  4-define_variables.py contains a script that define and annotate the following variables with the specified values:

  • a, an integer with a value of 1.
  • pi, a float with a value of 3.14.
  • i_understand_annotations, a boolean with a value of True.
  • school, a string with a value of “Holberton”.

• 5. Complex types - list of floats
  5-sum_list.py contains a type-annotated function sum_list which takes a list input_list of floats as argument and returns their sum as a float.

• 6. Complex types - mixed list
  6-sum_mixed_list.py contains a type-annotated function sum_mixed_list which takes a list mxd_lst of integers and floats and returns their sum as a float.

• 7. Complex types - string and int/float to tuple
  7-to_kv.py contains a type-annotated function to_kv that takes a string k and an int OR float v as arguments and returns a tuple. The first element of the tuple is the string k. The second element is the square of the int/float v and should be annotated as a float.

• 8. Complex types - functions
  8-make_multiplier.py contains a type-annotated function make_multiplier that takes a float multiplier as argument and returns a function that multiplies a float by multiplier.

• 9. Let's duck type an iterable object
  9-element_length.py contains an annotation of the function's (shown below) parameters and return values with the appropriate types.

  def element_length(lst):
    return [(i, len(i)) for i in lst]

• 10. Duck typing - first element of a sequence
  100-safe_first_element.py contains an augmentation of the following code with the correct duck-typed annotations:

  def safe_first_element(lst):
      if lst:
          return lst[0]
      else:
          return None

• 11. More involved type annotations
  101-safely_get_value.py contains a script that includes the code below with type annotations added to it.

  def safely_get_value(dct, key, default = None):
    if key in dct:
        return dct[key]
    else:
        return default

• 12. Type Checking
  102-type_checking.py contains the code below and uses mypy to validate it and apply any necessary changes.

  def zoom_array(lst: Tuple, factor: int = 2) -> Tuple:
    zoomed_in: Tuple = [
        item for item in lst
        for i in range(factor)
    ]
    return zoomed_in
  
  
  array = [12, 72, 91]
  
  zoom_2x = zoom_array(array)
  
  zoom_3x = zoom_array(array, 3.0)